2 things CS but you will have to check Axa policy.
1st I think you have to make a claim for special diet within 30 days if you are going to claim and
2nd you dont know at this point whether there will be further blood tests required within 12 month policy period and need to make a claim within 6 months for vet fees or otherwise you are still stuck with excess. Need to check this though.
Sorry I don't know if a claim affects the following year's premium or not. By the time we were claiming for Thomas, he was 18 and premium did get heavy but assumed age related. Heavy as it was, it was nowhere near the amounts we claimed back.
for Josh meanwhile and hope he's feeling OK in himself. Just saw your last post and pleased he's doing well