Advice on formula needed bees!

My DS is 6 months old next week, and has been EBF. I suspected he may be intolerant to dairy during his younger colicky days, so I cut it out around 8 weeks and haven't touched it since.

Anyway I am at the stage where I'd like to introduce a bit of formula into his life. I'll still carry on breastfeeding for as long as it's working for both of us, but I'd like a bit more flexibility - and I can't pump much as he guzzles everything I've got going! I've been giving him a few spoons of yoghurt each day for the last few days to see if dairy really is a problem, and I've noticed no reaction.

Even if as it seems he is fine with dairy, I'm a bit wary of how his tummy might react to suddenly introducing formula? I'm probably only looking at a max of 1 bottle per day at this stage, and ideally don't want to use a dairy free formula as I've heard taste can be an issue! But curious as to how did others made this transition - just give them a bottle and see what happens? Or mix it with some BM at first? And how did your LOs react to starting on it? I can't seem to find much info online about introducing a bit of formula to an older baby.

Thank you!!