@brnvince
A prepay plan is exactly that you choose a plan and prepay for the next 30 days of service. If you do not wish to continue service for the next 30 days you can disable autopay so the plan does not renew and you have a maximum 89/90 days to pay and reactivate before the account and Sim card gets canceled and deactivated.
If at anytime in the next 30 days you wish to change plans you can schedule a change plan on next renewal or choose to change immediately but this option means you forfeit the remaining days and services of the current plan with no prorating, credit or refund. It is only recommended when more than 1gb of mobile data is required. Autopay will only attempt to charge your registered payment card for the plan amount once every 30 days after debiting any available funds in your account balance first. Which plan are you considering? The $15 plan?
The preferred method by pm if you need a referral code for the $10 bonus credit is for you to choose a community member and send them a private message requesting their referral code. This prevents your private message box from being overrun with members sending you their referral code. Additionally unsolicited referral codes are against the community ToS and should not be used but rather reported but that is entirely up to you.
Given that you have just recieved your pm Sim card in the mail if you activate today and contact customer support and explain the late arrival of Sim card resulted in you missing the activation deadline to recieve the holiday gifts. If you ask nicely customer support may still add them to the account as a gesture of goodwill. As always though it's YMMV.
I recommend you take screenshots of each activation page to capture the info you provide along with the transaction summary at the end of a successful activation. I suggest that once you log into the self serve account and verify the account with the 2FA code that you disable 2FA on the profile page so you do not have to verify every time you log into the account.
