LLC Distribution Questions - Very New

I'm opening a multi-member LLC (only owned single ones before) and want to make sure that I'm understanding the situation correctly. LLC's are pass-through entities that require members to file their share of profits even if the profits are re-invested (aka no distributions are given). Can I simply make a distribution at tax time to cover each member's tax liability and retain the rest of the profits for re-investments? I assume that these distributions are tax free (since they are paying the taxes in the first place). Since the distributions have to be equal (aka you can't just give the exact amount that person owes according to their tax bracket as it may result in an un-even distribution proportion-wise, would it make sense to simply do a 30% distribution, or whatever the highest amount they can possibly be taxed on? Whats the standard practice? At what time of the year do these distributions usually get issued? I've read that filing taxes as an S-corp is often used to avoid paying SS/Medicare taxes on profit amounts that exceed salaries members can charge. For example, if Sally's share of the profit for year A is 100k, and the standard rate for the role she provides for the company is 50k, she can take 50k as salary and the remaining 50k as capital gains (which are exempt from SS/Medicare taxes). If that's the case, when can the company agree to pay her the salary? What if the company isn't expecting to make that much money and then is a position where it would be advantageous to file taxes as an S-corp, would it be ok to pay Sally's entire 50k salary at the last second? Or does the salary have to be paid bi-weekly or monthly for it to be considered an actual salary? Also, if there are any other things I need to know, regarding out of state taxing, sales taxes, etc, please let me know. I'm new to multi-member LLCs and can use all the advice I can get!