[mistral][keystone] Updating credentials and trusts

Hey team, Mistral is using keystone "trusts" in order to perform action on behalf of another customer. If I understand correctly the trust mechanism in keystone, it's related to a specific user_id. Imagine I want to update the user (and password) of the mistral service (mistral-api), then the user ID may change, so the trust will be broken. Is there any way to update the user of mistral-api without breaking the trusts? One answer is to not change the user, but only the password. But doing so will break my service for a moment (while I update the passwords in both services - keystone and mistral). Is there any other option? Regards, Arnaud - OVHcloud.