Radio Failsafe actived before timeout

I flew my drone some days ago and the radio failsafe activated near the ending. When I analyzed the flight log, I noticed the duration of the failsafe was shorter than the 0.5 s that is expected. According from the log, at 10:05.8 the Radio Failsafe message appeared while at 10:05.9 it was cleared.

Does the time associated with these message reflect the real interval between the start of failsafe and it clearing, or is there a delay, therefore making the failsafe higher than the timeout of 0.5s?

The log is below: