A 30-day plan is not a 1-month plan (excepting the 30-day months of April, June, September, and November), and a 90-day plan is not (ever) a 3-month plan, so plan renewal dates will often fall on different days of the month.
Autopay applies a $2 discount on 30-day plans, a $6 discount on 90-day plans. But it seems like Autopay and announcements about Community Rewards are assigned on a calendar-monthly basis, not a strictly 30-day basis, lol.
I've noticed that Public Mobile always collects my payment one day after payment is due, and they've even given me an extra day or two "free" service a couple times - I suspect because of stat long weekend vs business weekdays - but I wouldn't recommend banking under the assumption that these little gaps always occur.
If you don't pay when payment is due then your account and service could be suspended. Your plan might be terminated and have to be setup again from scratch (and if you have a "grandfathered" plan then it might be lost forever, though I'm unwilling to experiment with this). But you will not lose your number unless your account remains suspended for at least a full 90 days. I don't think Public Mobile assesses any "disconnection" or "reconnection" penalties, but you'd have to endure a few days without phone service (and possibly request assistance from PM staff) after paying up on a suspended account.
