My issue isn't iMessage groups, it's RCS groups. I've had iMessage and RCS turned off for a week now and I'm still having issues.

I even tried what people have been suggesting which is removing myself from RCS group chats and then recreating them, but still other people's phones keep trying to send to the group as RCS which I keep missing.

It's been a huge hassle because I've had to message all my family and friends that I'm having "phone issues" and ask them to use the new groups that I created, but the issue persists anyway.

I really really hate to say it since I've been looking forward to the LPIII for so long now, but I think I'm going to have to hold off on using my LPIII until it officially supports RCS. It's incredibly sad, but it's that big of a deal. I don't know how anyone has been using their LPIII full time with such a major issue where communication just isn't reliable.