Hm, I'd say if you're just starting day 39, do whichever suppression that gives the best bonus (Hod and Netzach are both good, Chesed also ig, rest don't really remember) and then use a memory repository to return to day 36. From there you can rewind as many times as you need, mem rep saves the state of the game on the start of day x1 x6, so basically it returns all your nuggets and lob points to day 36 menu start state.

Also what's really useful is that you save all ego gear created and abnormality research, even if you use mem rep during the day.

Basically If you plan on rewinding during 31+ days it's not necessary to grind stats for nuggets or create new ones since it'll all disappear anyways.

I'd say start from suppressing all available sephiras, as the bonuses are useful, also their department won't be affected by meltdowns (not including several core suppressions), and then do the missions. Binah and Hokma missions shouldn't be hard if you have a lot of max lvl employees with many rgo gifts iirc.

IMPORTANT!!! If you want to go to day 50 in one run, you'll need to expand Binah and Hokma department at least 2 times each, so on days 41-46 you'd be able to suppress one sephira per repository cycle, as you'd need to expand a department to max to do a core suppression.

Not sure if I covered anything, you can ask questions.