I require a 25% retainer to hold their wedding date. Then another payment around 4-5 months before the wedding. Then their final remaining balance is due 30 days before the wedding. I am sure they *might* be able to get your your images at the very least but if it were me, I'd also probably be charging a rush fee. I am sure this depends on the situation and the photographer so I can only speak for myself.
Wanting the payment before the wedding date is pretty standard though. If your photographer has good reviews and isn't just some random of the street I'd say you're in good hands.