Block a buyer late on to save auction?

[berto.uk2015]

I have a collect in person auction ending at 6pm today in UK.

Received a bid v. early this morning from buyer in Poland.

Messaged to remind buyer (new? no history or rep) that item is collection, not shipped.

Now have messages wondering if I can drive the items to friends in London, then later maybe deliver to Corby (150 mile round trip). I can't, just a private seller with a bad back.

If this bid stays and wins then the whole auction is void and I need to get fees refunded etc.

So: If buyer cannot/will not retract their bid can I block them at this late stage so that the auction can properly complete?

Any suggestions gratefully received, I'm not an experienced seller.

[plpmr]

you can cancel their bid[s] and then block them.