Your main coverage is the annual vet and surgical fees limit, and it depends on your plan:
This is the most we reimburse for vet and surgical fees in one policy year, after your co-payment and any deductible.
Does it reset? Yes. Your annual limit refreshes at the start of each new policy year when you renew on time. So if you have used part of it this year, renewing gives you a fresh limit for the next year.
A few other benefits sit outside this main limit and have their own caps, such as third party liability and, on Plus and Champion, burial or cremation. You can see all of these on your policy schedule.