I upgraded both of my 66U's to the .44 last night and started to experience dropping connections. I did a reset, reloaded the firmware and config, and still had the same issue. The Laptop would connect to the router, stay connected for 3-5 minutes and then bounce to the other router (other side of the house). If I tried to reconnect, it would not connect to the primary router (in the same room as the PC) and would only connect to the weaker signal.
I downgraded to .43 and router is rock solid, I connect fast and say connected.
I ran out of time to do more diagnostics. I plan to try again when I have a bit more time to play.
JDB