Travelling to from USA whilst K1 is being processed

[Kev & Phylis 0]

Hi everyone!

This is my first post, so I hope that this is the correct place to post questions

A bit of background:

I got engaged to Phylis at Christmas and she (the US citizen) applied for a K1 in January. On Feb 19th she received the approval (NOA2?). I understand that this will now be passed to the US embassy in London.

So I have a few questions:

How long does it usually take for the London Embassy to schedule an interview?

I have 3 trips booked to visit the USA in the next few months (beginning of April, mid May, and then end of July - for a family holiday with 2 of my daughters) What happens if the interview is scheduled before any of these planned visits? Can I still travel on the Visa Waiver scheme?

In April we are thinking of buying a property (off plan). Is this OK?

Once we get married, can I return to the UK before I move out permanently? How long does it usually take from the date of the marriage, to receieve my Green Card?

Sorry for so many questions

Thanks in advance,

Kevin