1) You have to wait until the one year anniversary (Aug 2008) before filing your 2007 US return. Don't bother running a pre-version, it's a waste of your time and effort. You could have a sudden funeral to attend and that will bollux up your calculations. Just sit tight until Aug 2008 has passed.
2) For 2008, the 330 days begins Aug 2007, so you will have met the 330 day requirement by the time you leave. Thus, no need to file on extension for 2008. However, E&Y will probably do it on ext anyway.
3) Your husband can only claim Physical Presence Test, not Bona Fide Residence Test. It sounds like that's what you're doing, so you've already addressed that issue.
4) You sound very RNOR to me.
5) E&Y will take their own sweet time. They will do a fantastic job. They'll get all the right/safest status chosen and get you the lowest tax possible. It's being done by somebody over in India who speaks ESL, so there's no one for you to get chummy with and ask questions. They should send you an organizer to enter your dates of entry and exit to and from the US and the UK. Put all your concerns in writing along with the organizer, and they will be addressed.