diff --git a/packages/anastasis-core/src/challenge-feedback-types.ts b/packages/anastasis-core/src/challenge-feedback-types.ts
index 30f42288f..a5fcc6be9 100644
--- a/packages/anastasis-core/src/challenge-feedback-types.ts
+++ b/packages/anastasis-core/src/challenge-feedback-types.ts
@@ -28,7 +28,7 @@ export enum ChallengeFeedbackStatus {
   TalerPayment = "taler-payment",
   Unsupported = "unsupported",
   RateLimitExceeded = "rate-limit-exceeded",
-  AuthIban = "auth-iban",
+  IbanInstructions = "iban-instructions",
   IncorrectAnswer = "incorrect-answer",
 }
 
@@ -93,7 +93,7 @@ export interface ChallengeFeedbackRateLimitExceeded {
  * IBAN bank transfer.
  */
 export interface ChallengeFeedbackBankTransferRequired {
-  state: ChallengeFeedbackStatus.AuthIban;
+  state: ChallengeFeedbackStatus.IbanInstructions;
 
   /**
    * Amount that should be transfered for a successful authentication.
diff --git a/packages/anastasis-core/src/index.ts b/packages/anastasis-core/src/index.ts
index 055f3fb62..012667879 100644
--- a/packages/anastasis-core/src/index.ts
+++ b/packages/anastasis-core/src/index.ts
@@ -1,3 +1,22 @@
+/*
+ This file is part of GNU Anastasis
+ (C) 2021-2022 Anastasis SARL
+
+ GNU Anastasis is free software; you can redistribute it and/or modify it under the
+ terms of the GNU Affero General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Anastasis is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License along with
+ GNU Anastasis; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Imports.
+ */
 import {
   AmountJson,
   AmountLike,
@@ -22,6 +41,7 @@ import {
   TalerSignaturePurpose,
   AbsoluteTime,
   URL,
+  j2s,
 } from "@gnu-taler/taler-util";
 import { anastasisData } from "./anastasis-data.js";
 import {
@@ -879,7 +899,7 @@ async function pollChallenges(
       );
       continue;
     }
-    if (feedback.state === ChallengeFeedbackStatus.AuthIban) {
+    if (feedback.state === ChallengeFeedbackStatus.IbanInstructions) {
       const s2 = await requestTruth(state, truth, {
         pin: feedback.answer_code,
       });
@@ -1080,7 +1100,7 @@ async function changeVersion(
 ): Promise<ReducerStateRecovery | ReducerStateError> {
   const st: ReducerStateRecovery = {
     ...state,
-    selected_version: args.selection,
+    selected_version: args,
   };
   return downloadPolicy(st);
 }
@@ -1147,9 +1167,10 @@ async function selectChallenge(
 
   if (resp.status === HttpStatusCode.Ok) {
     const respBodyJson = await resp.json();
+    logger.info(`validating ${j2s(respBodyJson)}`);
     const instr = codecForChallengeInstructionMessage().decode(respBodyJson);
     let feedback: ChallengeFeedback;
-    switch (instr.method) {
+    switch (instr.challenge_type) {
       case "FILE_WRITTEN": {
         feedback = {
           state: ChallengeFeedbackStatus.CodeInFile,
@@ -1160,12 +1181,12 @@ async function selectChallenge(
       }
       case "IBAN_WIRE": {
         feedback = {
-          state: ChallengeFeedbackStatus.AuthIban,
-          answer_code: instr.answer_code,
-          target_business_name: instr.business_name,
-          challenge_amount: instr.amount,
-          target_iban: instr.credit_iban,
-          wire_transfer_subject: instr.wire_transfer_subject,
+          state: ChallengeFeedbackStatus.IbanInstructions,
+          answer_code: instr.wire_details.answer_code,
+          target_business_name: instr.wire_details.business_name,
+          challenge_amount: instr.wire_details.challenge_amount,
+          target_iban: instr.wire_details.credit_iban,
+          wire_transfer_subject: instr.wire_details.wire_transfer_subject,
         };
         break;
       }
diff --git a/packages/anastasis-core/src/provider-types.ts b/packages/anastasis-core/src/provider-types.ts
index 4da62fc04..1724b0ed1 100644
--- a/packages/anastasis-core/src/provider-types.ts
+++ b/packages/anastasis-core/src/provider-types.ts
@@ -20,6 +20,7 @@ import {
   buildCodecForUnion,
   Codec,
   codecForAmountString,
+  codecForAny,
   codecForConstString,
   codecForNumber,
   codecForString,
@@ -137,32 +138,34 @@ export type ChallengeInstructionMessage =
 
 export interface IbanChallengeInstructionMessage {
   // What kind of challenge is this?
-  method: "IBAN_WIRE";
+  challenge_type: "IBAN_WIRE";
 
-  // How much should be wired?
-  amount: AmountString;
+  wire_details: {
+    // How much should be wired?
+    challenge_amount: AmountString;
 
-  // What is the target IBAN?
-  credit_iban: string;
+    // What is the target IBAN?
+    credit_iban: string;
 
-  // What is the receiver name?
-  business_name: string;
+    // What is the receiver name?
+    business_name: string;
 
-  // What is the expected wire transfer subject?
-  wire_transfer_subject: string;
+    // What is the expected wire transfer subject?
+    wire_transfer_subject: string;
 
-  // What is the numeric code (also part of the
-  // wire transfer subject) to be hashed when
-  // solving the challenge?
-  answer_code: number;
+    // What is the numeric code (also part of the
+    // wire transfer subject) to be hashed when
+    // solving the challenge?
+    answer_code: number;
 
-  // Hint about the origin account that must be used.
-  debit_account_hint: string;
+    // Hint about the origin account that must be used.
+    debit_account_hint: string;
+  };
 }
 
 export interface PinChallengeInstructionMessage {
   // What kind of challenge is this?
-  method: "TAN_SENT";
+  challenge_type: "TAN_SENT";
 
   // Where was the PIN code sent? Note that this
   // address will most likely have been obscured
@@ -172,7 +175,7 @@ export interface PinChallengeInstructionMessage {
 
 export interface FileChallengeInstructionMessage {
   // What kind of challenge is this?
-  method: "FILE_WRITTEN";
+  challenge_type: "FILE_WRITTEN";
 
   // Name of the file where the PIN code was written.
   filename: string;
@@ -181,33 +184,28 @@ export interface FileChallengeInstructionMessage {
 export const codecForFileChallengeInstructionMessage =
   (): Codec<FileChallengeInstructionMessage> =>
     buildCodecForObject<FileChallengeInstructionMessage>()
-      .property("method", codecForConstString("FILE_WRITTEN"))
+      .property("challenge_type", codecForConstString("FILE_WRITTEN"))
       .property("filename", codecForString())
       .build("FileChallengeInstructionMessage");
 
 export const codecForPinChallengeInstructionMessage =
   (): Codec<PinChallengeInstructionMessage> =>
     buildCodecForObject<PinChallengeInstructionMessage>()
-      .property("method", codecForConstString("TAN_SENT"))
+      .property("challenge_type", codecForConstString("TAN_SENT"))
       .property("tan_address_hint", codecForString())
       .build("PinChallengeInstructionMessage");
 
 export const codecForIbanChallengeInstructionMessage =
   (): Codec<IbanChallengeInstructionMessage> =>
     buildCodecForObject<IbanChallengeInstructionMessage>()
-      .property("method", codecForConstString("IBAN_WIRE"))
-      .property("amount", codecForAmountString())
-      .property("business_name", codecForString())
-      .property("credit_iban", codecForString())
-      .property("wire_transfer_subject", codecForString())
-      .property("answer_code", codecForNumber())
-      .property("debit_account_hint", codecForString())
+      .property("challenge_type", codecForConstString("IBAN_WIRE"))
+      .property("wire_details", codecForAny())
       .build("IbanChallengeInstructionMessage");
 
 export const codecForChallengeInstructionMessage =
   (): Codec<ChallengeInstructionMessage> =>
     buildCodecForUnion<ChallengeInstructionMessage>()
-      .discriminateOn("method")
+      .discriminateOn("challenge_type")
       .alternative("FILE_WRITTEN", codecForFileChallengeInstructionMessage())
       .alternative("IBAN_WIRE", codecForIbanChallengeInstructionMessage())
       .alternative("TAN_SENT", codecForPinChallengeInstructionMessage())
diff --git a/packages/anastasis-core/src/reducer-types.ts b/packages/anastasis-core/src/reducer-types.ts
index b7e3148cb..bb06ea7c3 100644
--- a/packages/anastasis-core/src/reducer-types.ts
+++ b/packages/anastasis-core/src/reducer-types.ts
@@ -221,7 +221,7 @@ export interface ReducerStateRecovery {
   /**
    * Explicitly selected version by the user.
    */
-  selected_version?: AggregatedPolicyMetaInfo;
+  selected_version?: SelectedVersionInfo;
 
   challenge_feedback?: { [uuid: string]: ChallengeFeedback };
 
@@ -464,10 +464,16 @@ export interface ActionArgsUpdateExpiration {
   expiration: TalerProtocolTimestamp;
 }
 
-export interface ActionArgsChangeVersion {
-  selection: AggregatedPolicyMetaInfo;
+export interface SelectedVersionInfo {
+  attribute_mask: number;
+  providers: {
+    url: string;
+    version: number;
+  }[];
 }
 
+export type ActionArgsChangeVersion = SelectedVersionInfo;
+
 export interface ActionArgsUpdatePolicy {
   policy_index: number;
   policy: PolicyMember[];
@@ -518,10 +524,8 @@ export interface DiscoveryResult {
   cursor?: DiscoveryCursor;
 }
 
-export const codecForActionArgsChangeVersion = () =>
-  buildCodecForObject<ActionArgsChangeVersion>()
-    .property("selection", codecForAny())
-    .build("ActionArgsChangeVersion");
+// FIXME: specify schema!
+export const codecForActionArgsChangeVersion = codecForAny;
 
 export const codecForPolicyMember = () =>
   buildCodecForObject<PolicyMember>()
diff --git a/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.stories.tsx b/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.stories.tsx
index 3d765aa86..1acb2470c 100644
--- a/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.stories.tsx
+++ b/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.stories.tsx
@@ -250,7 +250,7 @@ export const OnePolicyWithAllTheChallengesInDifferentState = createExample(
     challenge_feedback: {
       "uuid-1": { state: ChallengeFeedbackStatus.Solved.toString() },
       "uuid-3": {
-        state: ChallengeFeedbackStatus.AuthIban.toString(),
+        state: ChallengeFeedbackStatus.IbanInstructions.toString(),
         challenge_amount: "EUR:1",
         target_iban: "DE12345789000",
         target_business_name: "Data Loss Incorporated",
diff --git a/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.tsx b/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.tsx
index 6660e63de..84d2588e0 100644
--- a/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.tsx
+++ b/packages/anastasis-webui/src/pages/home/ChallengeOverviewScreen.tsx
@@ -16,7 +16,7 @@ function OverviewFeedbackDisplay(props: { feedback?: ChallengeFeedback }) {
   switch (feedback.state) {
     case ChallengeFeedbackStatus.Solved:
       return <div />;
-    case ChallengeFeedbackStatus.AuthIban:
+    case ChallengeFeedbackStatus.IbanInstructions:
       return null;
     case ChallengeFeedbackStatus.ServerFailure:
       return <div class="block has-text-danger">Server error.</div>;
@@ -173,7 +173,7 @@ export function ChallengeOverviewScreen(): VNode {
               case ChallengeFeedbackStatus.TruthUnknown:
               case ChallengeFeedbackStatus.RateLimitExceeded:
                 return <div />;
-              case ChallengeFeedbackStatus.AuthIban:
+              case ChallengeFeedbackStatus.IbanInstructions:
               case ChallengeFeedbackStatus.TalerPayment:
                 return (
                   <div>
diff --git a/packages/anastasis-webui/src/pages/home/SolveScreen.tsx b/packages/anastasis-webui/src/pages/home/SolveScreen.tsx
index 3691d1416..941bfb93b 100644
--- a/packages/anastasis-webui/src/pages/home/SolveScreen.tsx
+++ b/packages/anastasis-webui/src/pages/home/SolveScreen.tsx
@@ -32,7 +32,7 @@ export function SolveOverviewFeedbackDisplay(props: {
           ]}
         />
       );
-    case ChallengeFeedbackStatus.AuthIban:
+    case ChallengeFeedbackStatus.IbanInstructions:
       return (
         <Notifications
           notifications={[
diff --git a/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodEmailSolve.tsx b/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodEmailSolve.tsx
index 935b45a77..d7b5f31f7 100644
--- a/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodEmailSolve.tsx
+++ b/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodEmailSolve.tsx
@@ -1,5 +1,23 @@
+/*
+ This file is part of GNU Anastasis
+ (C) 2021-2022 Anastasis SARL
+
+ GNU Anastasis is free software; you can redistribute it and/or modify it under the
+ terms of the GNU Affero General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Anastasis is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License along with
+ GNU Anastasis; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Imports.
+ */
 import {
-  ChallengeFeedbackStatus,
   ChallengeInfo,
 } from "@gnu-taler/anastasis-core";
 import { h, VNode } from "preact";
diff --git a/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodQuestionSolve.stories.tsx b/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodQuestionSolve.stories.tsx
index 51d0a9993..5ba621b68 100644
--- a/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodQuestionSolve.stories.tsx
+++ b/packages/anastasis-webui/src/pages/home/authMethod/AuthMethodQuestionSolve.stories.tsx
@@ -158,7 +158,7 @@ export const TruthUnknownFeedback = createExample(TestedComponent[type].solve, {
 } as ReducerState);
 
 const ibanFeedback: ChallengeFeedbackBankTransferRequired = {
-  state: ChallengeFeedbackStatus.AuthIban,
+  state: ChallengeFeedbackStatus.IbanInstructions,
   challenge_amount: "EUR:1",
   target_iban: "DE12345789000",
   target_business_name: "Data Loss Incorporated",