Unfortunately, I cannot get stable 160MHz channels in Europe since the (now-fixed) upstream commit broke the 160MHz channels. The radio becomes intermittent after a few hours, without any obvious error messages available in the logs (at least with the standard verbose). The behavior is reproducible in both my AX3600 units. I had the proper country code configured in all radios and iw reg looked ok (similar to DE for all purposes). It is also not the 10min DFS wait, the radio goes up and is working fine -- until it isn't, goes up and down, maybe stays up, rinse and repeat.
Has anyone experienced this? The only way to have a stable operation with the latest snapshot is to use 80Mhz channels (currently change to channel 36, without DFS, and the default country == US). Reverting to stock or the snapshot of a few weeks ago fully restores regular operation and the full performance (i.e., near ~950 Mbps effective download rate vs. ~850 Mbps with 80MHz channels).
(PS: unfortunately, the fantastic AX3600 thread is now closed. That is a shame, as it was the best resource for issues such as this one)