Thanks for this PSA. I decided to block all internet access to the app based on this report and found, at least according to LittleSnitch, that there is some form of use of an analytics API not documented in the internet access policy. I downgraded to the last stable version linked in this thread (5.0.49 from last December) and don't see it using that connection, so I am wondering if it is added by the new owners.
To be fair, many applications use analytics for a variety of legitimate purposes, and it seems to generate little traffic in this case. However, given this very odd situation and the overall lack of communication about changes, I'll continue with the old version with blocked internet access until finding an alternative or getting more transparency from the new owners.