diff --git a/lib/hooks/thread-hooks.js b/lib/hooks/thread-hooks.js
--- a/lib/hooks/thread-hooks.js
+++ b/lib/hooks/thread-hooks.js
@@ -306,7 +306,7 @@
 }
 
 export type ChangeThreadMemberRolesInput = {
-  +threadID: string,
+  +threadInfo: ThreadInfo,
   +memberIDs: $ReadOnlyArray<string>,
   +newRole: string,
 };
@@ -320,8 +320,9 @@
     input: ChangeThreadMemberRolesInput,
   ) => Promise<ChangeThreadSettingsPayload>) =>
   async input => {
-    const { threadID, memberIDs, newRole } = input;
-    const keyserverID = extractKeyserverIDFromID(input.threadID);
+    const { threadInfo, memberIDs, newRole } = input;
+    const threadID = threadInfo.id;
+    const keyserverID = extractKeyserverIDFromID(threadID);
     const requests = {
       [keyserverID]: {
         threadID,
@@ -346,7 +347,31 @@
 function useChangeThreadMemberRoles(): (
   input: ChangeThreadMemberRolesInput,
 ) => Promise<ChangeThreadSettingsPayload> {
-  return useKeyserverCall(changeThreadMemberRoles);
+  const keyserverCall = useKeyserverCall(changeThreadMemberRoles);
+  const dispatchActionPromise = useDispatchActionPromise();
+  return React.useCallback(
+    async (input: ChangeThreadMemberRolesInput) => {
+      const { threadInfo, memberIDs, newRole } = input;
+      const protocol = threadSpecs[threadInfo.type].protocol();
+      invariant(
+        protocol.changeThreadMemberRoles,
+        `changeThreadMemberRoles not supported for thread type ` +
+          `${threadInfo.type}`,
+      );
+      return protocol.changeThreadMemberRoles(
+        {
+          threadInfo,
+          memberIDs,
+          newRole,
+        },
+        {
+          keyserverCall,
+          dispatchActionPromise,
+        },
+      );
+    },
+    [dispatchActionPromise, keyserverCall],
+  );
 }
 
 const newThinThread =
diff --git a/lib/shared/threads/protocols/keyserver-thread-protocol.js b/lib/shared/threads/protocols/keyserver-thread-protocol.js
--- a/lib/shared/threads/protocols/keyserver-thread-protocol.js
+++ b/lib/shared/threads/protocols/keyserver-thread-protocol.js
@@ -12,6 +12,7 @@
   sendReactionMessageActionTypes,
 } from '../../../actions/message-actions.js';
 import {
+  changeThreadMemberRolesActionTypes,
   changeThreadSettingsActionTypes,
   leaveThreadActionTypes,
   newThreadActionTypes,
@@ -116,6 +117,8 @@
   ProtocolDeleteMessageInput,
   JoinThreadUtils,
   ProtocolJoinThreadInput,
+  ProtocolChangeThreadMemberRolesInput,
+  ChangeThreadMemberRolesUtils,
 } from '../thread-spec.js';
 import { threadTypeIsSidebar } from '../thread-specs.js';
 
@@ -373,6 +376,26 @@
       await addMembersPromise;
     },
 
+    changeThreadMemberRoles: async (
+      input: ProtocolChangeThreadMemberRolesInput,
+      utils: ChangeThreadMemberRolesUtils,
+    ) => {
+      const { threadInfo, memberIDs, newRole } = input;
+
+      const promise = utils.keyserverCall({
+        threadInfo,
+        memberIDs,
+        newRole,
+      });
+
+      void utils.dispatchActionPromise(
+        changeThreadMemberRolesActionTypes,
+        promise,
+      );
+
+      return await promise;
+    },
+
     updateSubscription: (
       protocolInput: ProtocolUpdateSubscriptionInput,
       utils: UpdateSubscriptionUtils,
diff --git a/lib/shared/threads/thread-spec.js b/lib/shared/threads/thread-spec.js
--- a/lib/shared/threads/thread-spec.js
+++ b/lib/shared/threads/thread-spec.js
@@ -238,6 +238,16 @@
   +dispatchActionPromise: DispatchActionPromise,
 };
 
+export type ProtocolChangeThreadMemberRolesInput = {
+  +threadInfo: ThreadInfo,
+  +memberIDs: $ReadOnlyArray<string>,
+  +newRole: string,
+};
+export type ChangeThreadMemberRolesUtils = {
+  +keyserverCall: ProtocolChangeThreadMemberRolesInput => Promise<ChangeThreadSettingsPayload>,
+  +dispatchActionPromise: DispatchActionPromise,
+};
+
 export type ProtocolUpdateSubscriptionInput = {
   +input: UseUpdateSubscriptionInput,
   +viewerID: ?string,
@@ -374,6 +384,10 @@
     input: ProtocolAddThreadMembersInput,
     utils: AddThreadMembersUtils,
   ) => Promise<void>,
+  +changeThreadMemberRoles?: (
+    input: ProtocolChangeThreadMemberRolesInput,
+    utils: ChangeThreadMemberRolesUtils,
+  ) => Promise<ChangeThreadSettingsPayload>,
   +updateSubscription: (
     input: ProtocolUpdateSubscriptionInput,
     utils: UpdateSubscriptionUtils,
diff --git a/native/roles/change-roles-header-right-button.react.js b/native/roles/change-roles-header-right-button.react.js
--- a/native/roles/change-roles-header-right-button.react.js
+++ b/native/roles/change-roles-header-right-button.react.js
@@ -6,9 +6,7 @@
 import { Text, View } from 'react-native';
 import { TouchableOpacity } from 'react-native-gesture-handler';
 
-import { changeThreadMemberRolesActionTypes } from 'lib/actions/thread-action-types.js';
 import { useChangeThreadMemberRoles } from 'lib/hooks/thread-hooks.js';
-import { useDispatchActionPromise } from 'lib/utils/redux-promise-utils.js';
 
 import type { NavigationRoute } from '../navigation/route-names';
 import { useColors } from '../themes/colors.js';
@@ -26,8 +24,7 @@
   invariant(selectedRole, 'Expected selected role to be defined');
   const navigation = useNavigation();
 
-  const callChangeThreadMemberRoles = useChangeThreadMemberRoles();
-  const dispatchActionPromise = useDispatchActionPromise();
+  const changeThreadMemberRoles = useChangeThreadMemberRoles();
 
   const { disabledButton, purpleLink } = useColors();
   const textStyle = React.useMemo(
@@ -44,24 +41,20 @@
       return;
     }
 
-    void dispatchActionPromise(
-      changeThreadMemberRolesActionTypes,
-      callChangeThreadMemberRoles({
-        threadID: threadInfo.id,
-        memberIDs: [memberInfo.id],
-        newRole: selectedRole,
-      }),
-    );
+    void changeThreadMemberRoles({
+      threadInfo,
+      memberIDs: [memberInfo.id],
+      newRole: selectedRole,
+    });
 
     navigation.goBack();
   }, [
-    callChangeThreadMemberRoles,
-    dispatchActionPromise,
+    changeThreadMemberRoles,
     initialRole,
     memberInfo.id,
     navigation,
     selectedRole,
-    threadInfo.id,
+    threadInfo,
   ]);
 
   const saveButton = React.useMemo(() => {
diff --git a/web/modals/threads/members/change-member-role-modal.react.js b/web/modals/threads/members/change-member-role-modal.react.js
--- a/web/modals/threads/members/change-member-role-modal.react.js
+++ b/web/modals/threads/members/change-member-role-modal.react.js
@@ -3,7 +3,6 @@
 import invariant from 'invariant';
 import * as React from 'react';
 
-import { changeThreadMemberRolesActionTypes } from 'lib/actions/thread-action-types.js';
 import { useModalContext } from 'lib/components/modal-provider.react.js';
 import SWMansionIcon from 'lib/components/swmansion-icon.react.js';
 import { useChangeThreadMemberRoles } from 'lib/hooks/thread-hooks.js';
@@ -14,7 +13,6 @@
   ThreadInfo,
 } from 'lib/types/minimally-encoded-thread-permissions-types.js';
 import { values } from 'lib/utils/objects.js';
-import { useDispatchActionPromise } from 'lib/utils/redux-promise-utils.js';
 
 import css from './change-member-role-modal.css';
 import UserAvatar from '../../../avatars/user-avatar.react.js';
@@ -32,8 +30,7 @@
 function ChangeMemberRoleModal(props: ChangeMemberRoleModalProps): React.Node {
   const { memberInfo, threadInfo } = props;
   const { pushModal, popModal } = useModalContext();
-  const dispatchActionPromise = useDispatchActionPromise();
-  const callChangeThreadMemberRoles = useChangeThreadMemberRoles();
+  const changeThreadMemberRoles = useChangeThreadMemberRoles();
   const otherUsersButNoOtherAdminsValue = useSelector(
     otherUsersButNoOtherAdmins(threadInfo.id),
   );
@@ -86,26 +83,20 @@
       return;
     }
 
-    const createChangeThreadMemberRolesPromise = () =>
-      callChangeThreadMemberRoles({
-        threadID: threadInfo.id,
-        memberIDs: [memberInfo.id],
-        newRole: selectedRole,
-      });
+    void changeThreadMemberRoles({
+      threadInfo,
+      memberIDs: [memberInfo.id],
+      newRole: selectedRole,
+    });
 
-    void dispatchActionPromise(
-      changeThreadMemberRolesActionTypes,
-      createChangeThreadMemberRolesPromise(),
-    );
     popModal();
   }, [
-    callChangeThreadMemberRoles,
-    dispatchActionPromise,
+    changeThreadMemberRoles,
     initialSelectedRole,
     memberInfo.id,
     popModal,
     selectedRole,
-    threadInfo.id,
+    threadInfo,
   ]);
 
   const primaryButton = React.useMemo(