the default autosave timer should be changed from 20 seconds to something more convenient like 5-10-15 minuts
Also it makes the setting counter intuitive sice u dont expect the current value to be seconds

Actually the default is one hour.
Could you send a screenshot or logfile? Add it here https://forums.factorio.com/viewtopic.php?f=96&t=95271

well no idea how it happened, i just verified and yeah its set to one hour
But somehow yesterday i started 3 different maps and each time the timer value after loading the map was 0:00:20
tried to reproduce but no luck ... must have been another mod interacting ... its unfortunate i deleted all the saves (for the proper mod list); there was hundreds before i noticed it on the first map :D