Thanks! I noticed on one of my phones that RCS breaks once the Messages app is out of date by a certain amount of revisions. I hope this is an arbitrary decision by Google to invalidate older versions, given that the RCS protocol hasn't changed. I wouldn't want the Graphene team to have to keep up with each change Google makes with their Messages app, and instead is a security oversight Google has found in their own app.

We definitely will have to keep up with the changes. We already do in order to provide support for using RCS via Google Messages on GrapheneOS. Recently, they made a change which broke it on GrapheneOS and we had to quickly fix that in under a day.