Given the circumstances of not gathering in groups and not davening Ma’ariv after Tzeit on מצש״ק, would the Rosh Yeshiva recommend saying ברכת הלבנה at first sight of the new moon until ב״ה things change?
Absolutely. If you don’t say it in shul (as it were), no one will remember to say it. The language of Rema (Shulchan Arukh OC 426:1) is אין לקדש אלא בלילה בעת שהלבנה זורחת ונהנין מאורה – so:
- The language is not strictly saying it doesn’t count, just that one shouldn’t. And we should override that to make sure that the kahal says it. Like we allow early counting of the omer, to make sure that the kahal says it.
- You can rely on the Gra (Biur HaGra OC 261:2) that it is Tzeit 13 1/2 minutes after Shekiah. I imagine that you generally hit that if you started Ma’ariv after Shekiah. But even if it is before that, I would rely on #1.