Glad to have you here in the Community, @eric_holt.
I'll share a few details about moving your revenue from one month to another.
You can only use a single journal entry if the transactions are on the same date. In your case, QuickBooks will require you to match two separate journals since you're moving income between two months.
I'm including this helpful article to learn more about customer prepayments in the program: How to Record Customer Prepayments for Products or Services.
This will get the information you need for today, @eric_holt.
I'm here anytime you need anything else. Wishing you and your business continued success.