There isn't such a thing.
That's not insurance, it's a payment plan. To qualify as "insurance" you first must have something to insure...(your good health)
There is, however, such a thing as a pre-existing condition exclusion clause, which allows the insurer to write a policy which will cover everything except the named condition for a certain period of time.
If there is no recurrence within say 18 months, the condition will then be covered. Maine has (had) such a provision.
The answer is complete repeal, interstate competition, carrier-funded high risk pools and cumulative tax-free health savings accounts.
Providers also need serious reforms to stop the non-transparency of third-party billing and gouging of insurers and cash patients to pay for all the bad-debt and "free healthcare"
So how do the carriers fund these pools if not through everyone's insurance premiums?
What does this approach really buy us?