I think it's important to note that the primary reason the conservative party lost many of their seats is because their vote was split between them, and an even more right wing party led by Nigel Farage. It wasn't because of a huge shift to the left (or at least the centre left position the labour party occupy right now).
In my constituency for example, if you put the conservative + reform votes together, they would have beaten the nearest competitor by a country mile.