I noticed today that my GrapheneOS Pixel 7 (which has been working without problems for months, thanks!) keeps dropping every few minutes to my carrier's Edge network (indicated by E). If I disable 2G in Network, it loses the cell network connection completely.
I swapped SIMs with an iPhone 12 (unaffected by network issues) and the problems persist (GrapheneOS drops to 2.5G or completely, iPhone 12 works with GrapheneOS SIM).
It could be a hardware issue with my Pixel 7 or sudden compatibility issue w/ my carrier (a T-mobile reseller) but posting here in case anyone else experiencing issues. Would much rather not have to re-flash stock Android (as there's not yet an implemented GrapheneOS backup option).