Reliance on Prototype sponsor adopted amendments

[Guest CAG1]

Here's the situation...employer adopts a prototype plan for its GUST restatement. The prototype sponsor adopts all required interim amendments (through 401(a)(31)(B) on behalf of adopting employers in a timely manner. In spring of 2005, employer changes providers and adopts the new provider's prototype document. However, the provisions of the plan do not fit on the new providers prototype so it is amended and considered individually designed.

The employer did not adopt any interim amendments from 2005 through the present. Can this employer who amended out of prototype status nevertheless rely on the interim amendments adopted at the sponsor level post 2005?

Or, is a streamlined VCP required to cover the interim amendments post 2005?

Comments are appreciated.