Reading Phillip's post it sounds like a bit of daylight robbery is going on. So any car that is taxed and passed to trade will become 'un-taxed' on the 1st October with NO refund given. Despite the trade not being able to claim a refund on a tax disc the fact that it is tax'ed may have added value onto the price of the car,for example a 4x4 or sports car taken in part ex in July with best part of a years road tax costing £475, a dealer may have allowed an extra £300 in p/x because the tax had a 'value' to it. Come October that value is wiped out. Not a problem if DVLA has told us 12 months ago this would be the case but it seems a little wrong that something can become worthless overnight with such little notice.
Would be interesting if someone legally challenged the DVLA to recover the loss in value. Does the owner of the car own the tax, the last registered keeper, the DVLA? £millions worth of tax will become invalid and worthless overnight.
Imagine if a car company pulled the same trick and said warranties were valid for cars owned by the trade? It seems the same thing to me