I also live in the UK.
Why do you not contact GITRACE which is based here in the UK, they search mainly for fathers and grandfathers. It means you can circumvent the system as under a 1990 law, all children of GI fathers have a right to have their records, which applies to the UK Warbabes. There is an individual at NARA in Missouri that searches for the UK War Babes fathers.
You need to be aware that some documents were lost in a fire in NARA around 1972.
Contact me through Ancestry, I will get back to you.