Question for sleeping stretches at night & Breast Feeding

We are currently waking our baby boy up every 4 hours during the night to breastfeed and hope that at his doctors appointment next week we can start letting him sleep longer stretches at night because I definitely think he could go 5 ish hours at night.

My question is, do I need to do anything different to maintain supply? Will I need to get up between then and pump? I would love any tips and advice!