Going from ebf to formula, 6 mth old, in a right pickle!

[twolittleboysonetiredmum]

So, as title says, I'm in a confused pickle!
Ebf at 25 weeks and we're gradually moving to formula instead. Thinking one feed per week. Started a few days ago with 11:30 ish feed (basically pre that midday nap). Had a slight scare thinking she was allergic but GP confident it's just a viral rash. Anyway, I digress. I've just realised that this baby has no routine so I don't know what to do next! She's dc3 so you'd think I'd have a clue. She just eats as and when (boob) mainly when my other two give me 5 mins break I just grab her and stick boob in. She seems to be hungry every 2 hours ish but that needs stretching out a bit. Obviously we're also starting to wean but she's not eating much yet and won't be for a bit.
I don't know what to do! When roughly should she be having a bottle?! How frequently? How much? I don't know what feed to replace next as she's so random aside from that pre nap one. And should I be thinking about mealtimes too amongst it all?! Argh!
She also still feeds a lot at night. That's my last swap for formula as I hate making up bottles in the night.
So basically - what should a 6 month old day look like? Please!

If she's feeding roughly every 2 hours, this is a routine is it not?

I think the current advise is to drop one bf every 2 weeks. So go with the 11.30 formula feed for a couple of weeks and then think of swapping another feed, maybe the first feed?

As for food, there's not much of a worry, just offer her some if she's around when you are eating. According to the NHS she doesn't need to move to 3 meals a day until she's between 8 and 9 months, so there's no rush