Ceasing an EACA mid year

[30Rock]

We have a sponosr that wants to cease automatic enrollment mid plan year, and the plan was structured as an EACA with the 90 day permissive withdrawal feature and an annual escalator. It appears that an EACA is supposed to be based on a 12 month plan year unless the plan allows mid year entry for new hires, and then the 6 month extension on testing is lost, but the 90 day withdrawal can still be used for the new hires. But can the feature cease mid-year, provided the client does not use the 6 month extension?

Thanks!