Could everyone reading this with Catalyst AX series APs and a 9800 WLC do "show ap slots" and look for APs that have the slot 1 radio showing up as "802.11b/g" ? For example an affected AP will look like this in the output of "show ap slots":
ap-name 3 C9130AXI-B 802.11b/g 802.11b/g 802.11a
Seeing an issue on 17.9.3 (also happened once on 17.9.1) where there is apparently a 1/1000 or so chance that a Catalyst AX series AP will join the controller with regulatory domain mismatch on slot 1 even though the country code is set globally and in the AP join profile. Observed on C9130AXI-B here; other models may be affected.
Rebooting the affected AP works around the issue, but the problem is very hard to detect; the only way I've found of manually detecting it so far is to do "show ap slots" via SSH and look for slot 1 radios showing up as "802.11b/g" - which is not correct for the 9130AXI-B, or probably any Catalyst AP. DNAC doesn't throw an alarm about it, and the radio slot will be missing entirely from the output of "show ap dot11 5ghz summary".
This issue will cause affected APs to have a slot 1 5ghz dedicated radio out of operation until the AP is rebooted, which has caused a coverage complaint for me before where someone noticed on a stumbler that 5ghz coverage was bad in a particular area.
I have a TAC case open but since this issue doesn't happen very often - might need community help to get it noticed, and probably if others are experiencing it for them to open TAC cases as well.
