I would really reccomend the yianna bra from Amazon as a cheap alternative to Macom. I was 34a and had 450cc and the medium is perfect for me. It’s so comfy I bought 3 and only £15. I have Macom and it’s fine I wear it but I’m really not gonna rave about it and far prefer my yianna bras. I have a large Macom, bought the medium which fitted fine pre op but straight after surgery was never gonna get round my implants. I exchanged it for the large and I wear it now on the tightest clasp. You will be massively surprised at quite how much swelling you’ll have. I didn’t really realise it’s only when I’m tightening the breast band which I previously thought was so tight I couldn’t breathe, that I can see how much swelling has gone done. I would say the loose Asda bras will be perfect fit post op, but if I were you I would pick up an Amazon yianna for £15 in a medium and bring both op day.
I also totally agree ice packs and hot water bottle. I also have a lovely wheat pillow for neck. And I found a sippy cup with a straw was a real godsend those first few days too! Don’t be nervous you’ll be well prepared and we’ll looked after! X