If a leil tevilah falls out Motzai Shavuos in Israel where it follows shabbos and one day yom tov, does one need to do preparation on Friday or can one do the whole preparation on Motzai Yom Tov?
Answer:
Ideally she should begin the preparations on Erev Shabbos and complete them on Motzai Yom Tov, including redoing whatever needs to be redone such as showering another time before tevilla. Practically speaking for many women it is difficult to accomplish real chaffifah on Erev Shabbos in such a situation. If that is the case she may do the entire chafifah on Motzai Yom Tov, she should be careful to do it slowly and methodically with the complete preparations taking about an hour.