IMPORTANT Note:

You have already switched from EOY to RTI on the following On-boarding Date : 6th April 2015

From this date all your P45, P46 etc can be E-filed throught RTI FPS. You need not have efile EOY returns any more.

More information can be found in the HMRC link below: http://www.hmrc.gov.uk/rti/developerfaqs.htm#3