Wannabe,
Congrats on getting the sponsorship!
The exact requirements for your Class 1 medical can be found
here. However, if you've never needed glasses before, I wouldn't worry - I think it's extremely unlikely that your eyesight would deteriorate from not needing glasses at all, to being outside the limits, in such a short space of time.
If you are really concerned, you should contact the CAA at Gatwick for advice. They may be able to test your eyesight for you for a small fee, saving you (or your sponsor) the cost of the full Class 1, or even more, if your eyesight really is outside the limits.
It also seems only fair that you inform your sponsor if you have any worries. If you can't get a medical then you won't be able to complete the course whatever else happens, so you've got nothing to loose by letting them know straight away, but lots to gain in terms of good will.
Hope it all works out for you. And if not, then don't forget that a Class 2 medical is a lot less stringent, so you may still be able to fly for fun whilst finding a different career for yourself.
FFF
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