As far as i'm aware, the stations with Jet2.com staff are as follows;
LBA - Ticket Desk, Check-in staff and Ramp
MAN - Ticket Desk only - check-in by Aviance
NCL - Ticket Desk only - check in by Swissport(?)
AGP - Ticket Desk, Check-in staff and Ramp
PMI - Ticket Desk, Check-in staff and Ramp
MJV - Ticket Desk, Check-in staff and Ramp
TFS - Ticket Desk and Check-in staff
All other stations are handled by agents.