Hi Leigh and Sandra,
Hope you got on alright last week - nice to meet you in Murcia!
PW have 30 days to put right any issues identified during your snagging, so yes I think they can ask you to complete before ithe snagging has been done. But, they can't force you to complete without the Habitation Certificate. Not sure what date your completion was but if the Certificate had arrived by then, you would be expected to complete.
Did you complete last week then or did you grant Power of Attorney to your Solicitor to complete on your behalf?
Debbie and Paul