I get it as well and I am not on the beta version. I have several Christmas forums on my Tapatalk and this is what i get:
DLA: API Message
DIYC: API Message
PC: No msg
LOR: No msg
LSH: No msg
Holiday U: No msg
Quick Google search shows this being a problem on many forums across the web. The suggestion I keep seeing is that the admin for any forums getting the message should contact Tapatalk. They have a vested interest in people not getting error messages like this.