I am trying to write a function that calculates a time card

I want to "say" that if you punch in between 8:00 am and 8:08 am, the time
will read 8:00 am, if it is 8:09 am, then the time will read 8:15 am.

I tried: c11<=08:08, 8:00 am, 8:15 am but it does not work.

Any thoughts?