Just got off the phone with the IRS. I had submitted an anonymous EPCRS filing for a pro bono, not-for-profit client, which had maintained a 5305 SEP even though it had a pre-existing 403(b) plan.
The IRS agent initially believed that there was no employer eligibility failure! She checked with a supervisor, and the answer is now in transit.
I will update once I actually receive an answer.
The problem here is that there is no Code or regulatory citation for the proposition that the Form 5305 prohibition against maintaining both 5305 SEPs and "any other qualified plan" includes a prohibition against 403(b) plans.
Even the IRS manual uses only the stock phrase "any other qualified plan" restriction.
