Pull off checks
"From my time on Nimrods, I seem to remember doing 'pull off' checks with a device that checked that the probe would leave the drogue properly. This was done before every scheduled AAR trip."
S-H, you're correct. As part of a before flight servicing, the pull off checks are carried out if the aircraft is due to do an AAR sortie. The probe is also checked post flight.
Ground refuel through the probe is carried out after scheduled maintenace or any rectification work on said system.