I may have had this happen in our '24 AT4 but I was towing and thought it might have been a trailer connection issue. About 10 minutes into my trip I started getting the fast flashing on the right turn signal but no indication where the issue was. I didn't see a message on screen but didn't investigate either. I hadn't turned off the vehicle when I dropped the trailer but don't recall the fast flash happening after that (dropped trailer at a buddies place and continued home). The next morning it worked fine with the trailer reconnected and hasn't happened again since (about 400 miles since it happened now). I'll be taking our 5th wheel out this weekend and if anything happens I'll report back (fairly short trip but we'll see).
Edit: On another note, my truck has been slow to register that a trailer is connected (7 pin). If I connect the trailer, take a drive, shut the truck off, and restart it later, it will show a trailer connection fault. The first time it happened I unplugged and plugged it back in and it cleared instantly. The 2nd and 3rd time it cleared itself after 30-60 seconds (guesstimate). It has never disconnected while driving, just at initial start-up after already being connected and driven.