Pre-reg car service interval

I've just found out something that's worrying me about my car's service history and I'm now looking for some advice.

I bought a pre-reg Renault from Arnold Clark last July. At the time, I was told the only difference between new and pre-reg is that, for me, the warranty will be shorter because I lose the months between its registration and me buying it. In my case, the car was registered in March, i.e. 4 months (or so) before I bought it. I was fine with this and felt the saving on new was worth taking the risk that something might go wrong in the final 4 months of my PCP contract.

In the second week or so of June, the car's display started flashing "Service due in 30 days". I expected this so kept it in the back of my mind. When it changed last week to 10 days, I booked a service under my service plan.

I've since found out, however, that a service "clock" starts from registration, not purchase.

This is concerning. If I'm 4 months late for the first service, that means I'm almost certainly in breach of the warranty conditions. But 1) I was never told this when buying; and 2) the car itself is only reporting it needs a service now - 1 year after purchase, not registration. So clearly the "clock" was reset to co-incide with my purchase/delivery date (I'm nowhere near the mileage limit for a service).

Can anyone advise on where I stand? Is it possible that Arnold Clark's pre-delivery checks allow them to reset the clock? Or have I been deceived?

I'll admit to a little naivety when buying the car; it was the first time I'd bought (nearly) new and definitely missed a few key questions. I was daft, but lesson learned, and mistakes won't be repeated in future. Nevertheless, I would still have expected the car itself to accurately report when its service is due. It shouldn't necessarily be relied upon, but that fact it is reporting in July when I purchased in July does seem a bit iffy.