Yungerman: If you start growing a beard then you’ll look bad for a few Shabbosim, but that’s part of growing a beard so there’s no other choice. I am not growing a beard. An Avel does not shave Erev Shabbos B’soch Shloshim, but it’s very hard to say that we treat Sefirah like Shloshim. We probably treat it like Aveilus 12 Chodesh, at which the point for shaving is Ad Sheyiga’er Bo Chaveiro. Trust me, my beard’s at that point. (Not that I hold that that last point is relevant anyway as a Minhag can’t trump the D’rabannan of Kavod Shabbos.)
147: It’s only Muttar to shave on Yom Ha’atzma’ut if you say Hallel (or, at least, it should only be).