Accommodating an early check in or a late check out is totally up to you!
If your schedule can't accommodate this, no worries - your listing is super clear on when check in and check-out times are! You can let your guest know it isn't possible.
If your guest asks well in advance of their reservation, you can tell them you'll need the time to get the space prepared for them or your next guest, and it may not be possible. You can always let them know to ask a little later if your schedule will work, and if it does, it'll be a nice surprise!