Address issues

Long story short, I am moving from Wales to London in July/August so I can attend a PGCE course down there. I've had to transfer from SFW to SFE because the course only accepts applications from SFE.
I posted my application maybe a month ago and haven't heard anything so I assumed it was all fine. Then this morning I had an email saying my application is incomplete. When I went to check it, it said I've completed all my actions and the site wouldn't let me complete the section that says 'incomplete'.
I called SFE and they said that just yesterday it was flagged as having an 'error' in the address. I know I didn't make an error in the address and it was the same throughout the application. I am really hoping the 'error' isn't that it's a Welsh address - I was told I could change it when I moved down to London through a CO1 form...
Either way I can't give an English address until I move and that's not until July at the earliest and by then I can't apply and still get funding by September can I?

I don't think I quite understand..
Do you mean its fine with my Wales address and it won't be rejected?
If it takes ~7 weeks to process how is it going to be ready by September if the soonest I can submit an application with an English address is on say the 11th August??

I have family already living around London, would I be able to list their address for now (so the application gets processed) then when I have my new address I can just update it and it wouldn't mess up the timeline?