Pumping and breastfeeding

Lisa • Pregnant with our first baby boy 💙 due sept. 14, 2015. 👼
Hi ladies, 
I have a question. I plan on exclusively breastfeeding our son when he's born , however I still would like to build up a supply in the freezer in case my husband wants to feed him or one of my family members or if I'm not home. 
Do any of you plan on breastfeeding mostly
But still pumping for that reason? How often do you plan on pumping? Once a day? Twice a day. From what I have been reading it looks like you can breastfeed your baby then within 20 mins after, pump so it's not interrupting their next feeding. Does this seem right? It's all kinda confusing to
Me! My plan is to breastfeed for 15-20 mins on one breast, burp and change baby to keep him up, then switch breasts so I'm not getting engorged and then breastfeed him on that breast and burp him again. After that I was going to pump. What are your plans?