Not quite sure on this question, but I will have a guess here.
I think they might be referring to level 4.
ATA 104 lays out the definitions of training levels
Level1 typically a Gen Fam
Level 2 Ramp /Transit
Level 3 Line & Base Maint
Level 4 Specialist Training
In this case it might be what specialist engine training you have received.
On the other hand my guess could be completely wrong and I'll go stand in the corner