I did a drop of research.. there's no question that said project needs to be done. Nice that they're trying to at least pretend to minimize the impact, but I'm not convinced it won't be a disaster full few months.. seems silly not to add more rooms..
Just seeing this now, It seems everyone agrees the only solution is to anticipate that demand will grow and start building more
BEFORE you need it.
In the meantime, one band-aid hasn't been discussed:
How many minutes after shkiya will the Lakewood Mikvahs allow someone to go?
Maybe we can have Sfardim go before Ashkenazim, as they hold you can start earlier. This will free up more appointments throughout the night.
On a separate note, I'm not a Rav, but if the alternative is 1AM, or pushing off to the next night, there may be room for leniency in starting closer to shkiya.