You should wait until they are completely healed and their hormones have settled down before working to bond them. For healing, they should be in a restricted space for 2 weeks, small enough that they can’t run and with nothing to jump up on. It seems cruel, but the spay surgery is pretty invasive, and they can pull internal sutures if they run or jump too soon. And remember it’s only temporary! So, you could use the x-pen for each of them, but set up to make it a bit smaller (half size would probably be fine). They will appreciate lots of extra toys and pets during that time!

Make sure your vet sends you home with some pain meds, and supplies for syringe feeding if needed. Some buns eat right away, others might need to be syringe fed a couple of times after they wake up. Usually if they don’t start eating on their own within 4-6 hours of waking up you should syringe feed. Your vet can prob give you critical care and syringes for this.  Your vet will also have you check on their sutures daily, where you just look to make sure there isn’t serious swelling, weeping, redness, or that they’ve been picking at them. Bunnies with proper pain management usually don’t need cones, but occasionally a bunny will need to be coned if they really wont stop messing with their sutures.

In terms of hormones, it can be a bit variable, but 3 weeks is the minimum. So after 3 weeks, you could start doing side swaps and pre-bonding and see how they react. If they seem calm with the switching, you could try some bonding sessions and see how they react. If they are immediately aggressive, I would wait longer and do more pre-bonding.