An employer/plan sponsor has an SEP that allows for immediate eligibility at which time employer is the only participant. Upon hiring two new employees, the employees are not included within the SEP, and the employer has never included the elgible employees within the SEP. I realize that correction cannot occur under EPCRS. I have been searching for authority but can find no guidance on how to correct this problem. Should employer pursue a closing agreement under IRC § 7121? Any advice on how to fix this error would be appreciated.