Fruit of the Loomwomens Wireless Push-up Bra Push Up Bra (pack of 2)

Q: Does the band roll up on this bra?

I have not had the band roll up even once ..in fact most of the time I don't even feel like the bra is there , it's just that comfortable !! Love them !

Q: The ft640 that i have is sized 36dd/38d but those sizes are listed separately in this listing. how are these bras sized??

I'm a 34 B and ordered 34B. The bra came with 2 sizes printed on it, 34 B and it's 'sister size' 36 A. The cups were good but overall the bra felt way too tight. I plan on sizing up in the band to see if that helps. It sounds like the FT640 also shows sister sizes. I would suggest then either trying a 38dd or 40d to start.