Your input is greatly appreciated.

Client has Sch C and we filed return with max SEP when it should have been as 401k (solo).

I've recalculated it with EE and ER amounts broken out and results are the same. My question is, if they keep the same payment calculated under the SEP, do I need to file an amended return? Wondering if there is some specific schedule that gets included with the return that would require me to amend.

Could be they want to amend since they can contribute more but wanted to know this part before I provide them with options.

OR the answer may be simply, amend to be on the safe side.