If you can bear to be patient and look out on bare earth for a little while longer, I would. The middle of summer is not a good time to lay turf, especially if you are in a hosepipe ban area as it really needs to be regularly watered in to stop the roots drying out and the grass turning brown. You could find that if you go away on holiday for a fortnight fairly soon, you might return to a completely brown dead lawn which would be a completely waste of your time and money.