I'm a bit lost. If you feel that the fan needs to be on for 10 mins (or whatever) to clear the room of steam, why not set the timer delay to 10 mins, rather than setting it to 60 seconds and then have to do (and remember to do) the switching manually to get the 10 minutes running?Agreed. If I chose the 60 seconds overrun set up then the fan would just be used in a different way, finish using the bathroom, turn fan on, go and do other stuff for ten minutes then come back and turn it off. I wouldn't rely on one minute being enough to clear a room of steam. It's not an optimal solution as it relies on remembering to turn it off after the desired operating time, but it would do the job.
Kind Regards, John