Q. If someone keeps the shitas Haari (the opinion of the Arizal that one does not shave during the whole sefira period), can he shave already on Erev Shavuos after Maariv?
A. Pekudas Elozor (O.H. 493: 2) mentions that Horav Chaim Vital zt’l himself would shave on Erev Sahavuos after Maariv. However, Moed Lechol Chai (6: 7) maintains that one should not shave at night, since it is a time of din (judgment).
Horav Shlomo Miller’s Shlit’a opinion is that one can be lenient.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit’a