Personally I wouldn't worry as the grease from the kingpin and the stub axle nipples end up in the same place.
Also you shouldn't need to bleed the system as the grease gun should exercise enough pressure to expunge the air out.
I use heavy oil on the kingpin nipples and I know when it's full as it produces a hydraulic lock - that is the gun goes solid and it's virtually impossible to push anymore in.
Grease the stub axle nipples and go enjoy your holiday.
