Be warned - the Screwfix approach to Customer Service includes the trick of bringing forward their "cutoff" time for orders without bothering to tell anyone.
Read their catalogue, and it will tell you the deadline is 1800 weekdays and 1400 Sunday.
But yesterday (Sunday) it turns out that any order placed in the last three-and-a-half-hours before the dealine (ie after 1030) missed the "next-day" delivery. Apparently mid-August is a "really busy time" for them.
Screwfix don't have the wit (or inclination) to warn customers when they place the order that their delivery standard cannot be met, nor do they bother to email you later in the day to say that they have failed to despatch on time. They just sit tight and leave you to hang around the next day waiting for delivery a parcel that hasn't even yet left Yeovil.
John Geddes Derbyshire