Have you examined your postpartum/non-maternity wardrobe yet for breastfeeding compatibility?
'Cause that was a shock to me after having my first baby. I'd been SO looking forward to having a waist again and getting to wear dresses... and then I went "Wait, hang on, there's no BFing access!" Which I really should have thought about sooner, but... yeah.
A lot of people are more comfortable lifting a top (say a T-shirt) up to breastfeed. For some reason I'm not; I feel more exposed that way. I prefer to access from the top, as it were - unbuttoning the top buttons of a button-up shirt, for instance. (It might be partly a vanity thing... my decolletage is far less unsightly than my postpartum tummy!) Of course, you can cover your tummy by wearing a Belly Band-type device if you prefer, but in summer?
So, yeah. Have a look through your clothes and see what you have. Most dresses will be out. Shirt-dresses, dresses that zip down the front, or really deep stretchy V-necks might work OK. Hoodies, buttoned/zippered shirts and so on are fine, with or without a nursing tank underneath. Tight shirts with built-in cups probably won't work, at least not without alteration.
It's worth trying stuff on (well, as well as you can with a bump in the way!) and seeing how far you can pull, say, a V-neck down or to the side to access a breast. Some fabrics are surprisingly stretchy; others not so much. And you want a decent amount of 'give', because there's nothing more annoying than a shirt trying to 'ping' back into position, scraping against the side of the baby's mouth while it's feeding a barely-accessible nipple!
Weird things to think about, I know.
But better to figure it out now than when you're newly postpartum and out of clothes! Nursing tanks are a good staple.
Incidentally, I'm a B-cup and it's really hard to find nursing bras in my size. It seems bra manufacturers assume that if you're lactating, you're huge. Which, yeah, is the case for a lot of people, but not EVERYONE! It's very annoying.