...bit more info: ap which were disassociated yesterday evening has been now associated back to vc and other ap has been disassociated form vc.
Wired network has not been changed since last summer and all of those 13 pcs ap's are connected to two switches and there has been problems with ap's connected to both switches so I assume there is no problems in switch network.
EDIT: I added remote syslog yesterday to vc and today between 16:01 and 16:24 I got HUGE "throwup" of log messages (total of 348Mb) from two ap's where most of the log entries are like this:
2020-01-21 16:01:10 - 2020(err) AP:ap-107-aa:b6 <10.10.0.107 34:FC:B9:C8:AA:B6> cli[5990]: PAPI_Send: sendto AP CLI failed: (null) Message Code 0 Sequence Num is 28799
2020-01-21 16:01:10 - 2020(err) AP:ap-107-aa:b6 <10.10.0.107 34:FC:B9:C8:AA:B6> cli[5990]: sendAck: sendto 6c000a0a:24635 failed: Resource temporarily unavailable