Hi Lewis,
Like DVR6K my eyesight was outside the limits for an Initial Class 1 medical but inside them for the renewal. Having provided my prescription for the last few years to the CAA to show the stability of my eyesight I was issued witha Class 1 Medical with Deviation.
The deviation is considered on an individual basis depending on your past records and is then removed from your medical once your commercial training is completed as you will then be renewing your medical each year.
Hope it works out for you and good luck!