What a co-incidence
I've just had this exact discussion with the DVLA, and they won't budge on the way that they record license categories. They claimed to be unaware that anyone had had an issue with insurance because of it - I have the emails available if anyone is interested.
I do have to take issue with the use of the term "full license" here, because while many insurers do stitch us up by only listing "provisional" and "full" (or some other nonsense term), eBike are one of the few outfits that do allow us to distinguish between provisional, A1, "A2" (no such category exists, they presumably mean "A <= 25k") and A, so they're very slightly less despicable than most other insurers pulling this trick.
If you do get stung with this, take a very careful look at what your insurer asked. Some of them do ask for the date that you passed your test and so can jog on, and some only let us enter "full" (or "A") and are also on a sticky wicket - how are you meant to tell them that you've got "A1" or "A <= 25kW", and how on earth can your license category upgrading lose you 2 years of experience? Ambiguity in a contract, especially a contract of adhesion, should be decided in favour of the party that didn't draft it, they shouldn't be given a chance to turn round later and say "Oh, right, what we meant to ask you was..."
OK, eBike do actually ask the right question, but boo sucks to the Ombudsman, and I hope that someone with a more ambiguous insurer takes this to a proper grown up court which should throw it out on its ear if there's any vagueness in what was asked.
It's the insurers' ostensible job to get this right, and they've got absolutely no excuse for pleading ignorance since the Directive that defined the "A <= 25kW" license was published in 1991. We shouldn't need to still be explaining the correct license terminology to them over 21 years later.