Teething troubles - Fabia seats

Hi

I've just bought an 02 Fabia estate as a replacement for my old Felicia and have developed a few niggles. I've sorted the rear screen wash and worked out what's needed to sort intermittent reverse lights and temperature gauge thanks to this site.

My question though, is about the rear seats:

The rear doors have been leaking and the rear seats are mouldy so I am taking them out to clean. All are out except the larger of the backrests - the handle doesn't release it and feels like it's disconnected inside. Is there a way to free this half of the seat without cutting the fabric to get at the internals?

Thanks

Mitch