I know the oil seal in the stub axle has failed and the bearings are swimming in it.will just changing the inner hub seal stop the swivel grease getting on the disc or do I have change the stub seal as well.i was only going to change the pads..."should only take an hour with tea at half time"..how many times have I got that right just finished a night shift and bin at it for 3 hours .had to take the caliper off to get the pistons back in with a g clamp, badly rusted brake pipe fitting snapped the pipe made new one then no brake fluid at bleed nipple blocked bleed galley cleared with a small drill bit and clean off all the grease from the disc.now swollen with tea tied and pi**ed off.going to bed now zzzzzzz zzzzzzz zzzzzzzz

We are talking about wheel bearing grease here not the CV joint grease? You say in the stub axle do you mean the one that runs on the outer surface? If the hub seal has gone then you can just swap that but check there isn't corrosion on the seal land on the stub axle. If there is you can sometimes clean the surface up with a bit of fine grade abrasive tape or paper.

The grease on the inside edge of the disc is black probably a mix of wheel bearing grease and CV one shot .did have some play in the wheel bearing probably didn't help the seal.stub axle the bit the disc hub sits on via wheel bearings.will just changing the hub seal stop this leak as no point putting in new pads till this is fixed.