We have a bassinet booked in WTP so I presume that will be at a bulkhead?
Yes.
Is someone 'designated' to assist or is it anyone in the cabin?
All crew will help out.
What brand of water is carried as we can't decide whether to take ready-made formula or powder, bottle feeding obviously!
Various brands, including Highland Spring.
If we go the powder route, should we bring our own water or is there plenty available on board?
Plenty of water onboard.
Is there steam sterilizing facilities or would our own chemical solution be a better plan?
No. You're the best judge on the second one.
Can bottles be heated?
Yes.
Can bottles be refridgerated?
Not really.