I can't tell if you are talking about balancing or if you are talking about planning ahead but you can always leave space and be on the same leg again.
If A is red and you need to move it below a 2 pole, then,
2 pole breaker added
space
A-Red again.
Or move it to the other side and land it on A. Same difference. That is why you try and leave a little extra in a box or in the panel when you are roughing things out.
Or if you messed up and didn't plan ahead at all, then use some phase tape and reidentify it.
If you need to move it again... well then... I think there is a planning issue afoot. Or just pick the next single pole location where the color matches... I don't think I have ever seen a rainbow. Just a little thinking and planning ahead should keep that from happening. The rainbows come in when you have people buying pink, purple, and other weird colors because they were on sale.