Anyone switch from bottle to breast fed at 6 months or later?

-T-

Long story short:  I have always wanted to breastfeed my kids. Well, that didn't exactly work out due to my son being in the nicu and getting a gtube. I do pump and plan to do so until at least a year. Dr.'s do not want him to take anything by mouth until his reflux gets a LOT better. I was wondering if anyone has experience with getting their child to latch later in life? I would love to eventually get him to breast but I'm not sure if that will be possible since he has never done it.