Delaying your hefsek taharah in this situation is permissible, although you should discuss it with your husband. Assuming that you do not usually spot or have difficulty completing the clean days, this should not present halachic difficulties.

Do take the time, however, to work out if there would be any way to arrange immersion discreetly, even with family in town. Performing your hefsek taharah on time would leave open this possibility, and allow you to take advantage of any unexpected opportunities. Delaying immersion after completion of the clean days is no worse (some would say it is better) than delaying a hefsek taharah.

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