I also wonder how many PPLs tune into either the airfield ATIS or appropriate VOLMET (although Blackpool itself isn't on VOLMET) whilst en-route.
I fly regularly out of Blackpool, depending on my altitude I have been able to get Blackpool's ATIS when positioned South of Hawarden and maybe even Sleap (although haven't been there for a while so will try again next time). I think it would be fair to say that they had sufficient opportunity to get weather info for Blackpool well before their arrival.
I believe on the day in question it was only fogged in on the west coast as far south as Liverpool and maybe down the Dee towards Hawarden, 30-40nm South of Blackpool, plenty of possible alternates from that area with that range, hindsight again I know.