We definitely support that! You can set any number of flexible work zones during your day, and it'll even send you an alert if you work too long in a zone you said you wanted for recharge time. :)
Your signup flow, though, has a start time + end time and doesn't make it clear you can add these windows in. It made me pause during sign-up and I wonder if it would cause other folks to drop off. Maybe could be solved with copy somewhere even?
Similarly, as far as I can tell the signup flow does not let me add half hour increments (e.g 8:30am - 6:30pm). I also can't figure out how to add that even in-app.