in some cases you may be able to hold onto a plan that doesn't meet the law's requirements for as much as another year. after that however all plans must comply fully with the law and you'll need to select a new plan.
will all pre-existing plans be required to meet the aca requirements? . or might you be able to keep your plan as is -- e. g. without drug coverage if you don't need drug coverage and it is not being offered now?