Hi Alan, congrats on your purchase!
The 7 forums on here are pretty quiet; the best ones I've found are the 7 Series Register ones.
I'm not exactly sure what could be causing your problem, but I seem to remember seeing something about a dodgy valve in the oil canister which lets all the oil drain out of the canister/ filter area so it takes slightly longer than normal to bring the pressure up when cold starting.
Or I could be talking mince!