For both Asheknazim and Sephardim, immersion on any night should take place after nightfall, tzeit hakochavim. However, Sephardi practice on Friday night is to immerse after sunset but before tzeit hakochavim. We suggest that you check your local times and contact the mikveh to see if they could accommodate your immersion after tzeit hakochavim.

If that is too difficult to work out with them, you may immerse earlier, so long as your immersion is after sunset, shekiah. In that case, you should avoid seeing your husband at home until after tzeit hakochavim.

Shabbat shalom!