Just to add another data point, I received a new AT-6666Pro yesterday (via Amazon). It came with version 1.01 firmware installed.
The version 1.02 test data tool gave a "communitation error" on radio read (data cable had a CH343 chip). Installed the 1.03 version tool & it read with no trouble so I have a good backup of my original settings.
I did see the issue of disappearing M/N/O bands while testing with CPS 2.05. I.E. if you save read radio data, close the CPS program & restart it, when you read the data back, M/N/O are gone, CPS pull down list only goes through "L". If you read from the radio first, then read the saved data, M/N/O are present in the CPS pull down list.
I'm still doing familiarization/backups. I'll probably do some xmit tests into a dummy load next for baseline & to verify function.
BTW It was a " prime spring deal" from one vendor at Amazon for $254.
https://www.amazon.com/dp/B0D9CVXQR3?tag=worradfor-20