SCP or VCP for Incorrectly Checked ASG Box?

[Guest Los]

Client completed a volume submitter 401(k) profit sharing plan adoption agreement in 2008 and mistakenly checked "no" in response to whether it was part of an ASG. Client also checked a box that no other employers could adopt the plan as participating employers. Another entity's employees have been participating in client's plan since 2008, and I have determined that client and the other entity whose employees have been participating in the client's plan are indeed an ASG.

Thus, it would seem the other entity's employees should have been eligible to participate (as they have since 2008) in client's plan, but the document does not provide for their participation due to the erroneous adoption agreement. Is it possible for client to avail itself of SCP and simply adopt a resolution amending the original adoption agreement to conform the plan document to the plan's operation since 2008, or would a VCP filing be necessary?

I have used VCP for correcting unrelated employer/adopting employer issues, but I've not dealt with this fact pattern in the past.

[QDROphile]

SCP is not available for correction by plan amendment.