Do exactly as Redsnail suggest's,get in contact witht he CAA medical branch directly.Send them in you opticians report.
My own personal story is one of eyesight problems too.My figures from memory was LEFT -3.75 RIGHT -5.25 dioptres.In effect after speaking to a AME he said it was my right eye failing the initial class 1 limits.However upon reading through the CAA eyeight requirements they do state
"if your eyesight is within the renewal/revalidation standards get in touch!"
Therefore I duely got in contact and after some lengthy correspondence back and forth between me and the CAA they have given me a medical deviation for the distance vision.And as such next week I have my Initial Class 1 medical and assumming everything else with me is fine then I'd be issued with a Class1 with deviation.This would entitle me to have the medical,do my training and upon completion of my training the deviation would be lifted.I myself have an astigmatism so maybe you should look into this.If its too bad I know my eyesight was perfectly well and good for the FAA licence and was my back-up plan.
Hope all goes well
Regards