Parsons...
Thanks for the reply, I feared it may be the case.
I'm sorry to say i was 'that guy' who asked before bothering his arse to look for the info!
I did find this on the CAA website
Otorhinolaryngology guidance material GM | UK Civil Aviation Authority
And it says for initial validation hearing aids are not usually acceptable, but afterwards as you say the standards drop.
Not very clear, but i guess I'll apply and see what they say! Nothing ventured, nothing gained.
Thanks.