QNEC - missed deferrals

[hunter001]

Under the most recent EPCR rules to correct missed deferrals how is it determined if a QNEC needs to be made if the period missed overlaps a year end. EX. participant elected to defer effective 10/1/15 and was missed and deferrals implemented 3/1/16. Is a QNEC required for 10/1/15-12/31/15 period and because of the brief 3 month exclusion no QNEC required for 1/1/16-3/1/16 period?

What does the "rolling 3-month period mean". Under the above circumstances does this mean a QNEC would be required for the entire period 10/1/15-3/1/16?