Wheels dropped off for refurb this morning; will see them in 3 weeks

Got an annoying vibration at around 70mph which increases

I've swapped the wheels back to front, had all the wheels balanced and made sure the pressures are ok but its still there so I'm a little stumped
Didn't have the vibration with the old wheels on so i'm hoping it might be the winter tyres otherwise it could be a wheel bearing

Will be pissed if it is as its got less than 28K on the clock
On a happier note, gave it a good clean inside and out so it doesn't look like winter has pissed all over it!!