I think I had a similar issue with VHI. Hard to know they change things so often and make it so complicated. They changed the name of the plan, I was on, reduced what it offered, then introduced a new plan with the same name as the one I was originally on. When I queried it as I was told the plans are only valid for 12 months, when you renew it, you renew under the new terms for that plan for another 12 months. They don't roll over. In the past there was only a handful of plans and they didn't change that often, so this wasn't really an issue.
Now its like car insurance, you have to shop around each year, and be careful to check they haven't change what the plan offers in the meanwhile. The so man plans and options its almost impossible to compare them.