Sfix have just emailed as below.
Part of me thinks there could be some legitimacy. Bit the other half of me suspects you have all received the same thing! (Well, those that use Sfix and so they know your email addies.)
It isn't going to help me (or them!) - I simply do not need anything sufficiently to spend 50 quid in the next couple of days. Simple sceptical...
(Anyway, there site is always a problem these days.)
Dear Customer
We believe you may have recently experienced problems with our website and would like to offer you 10% off your next order over £50 using the voucher below.
You must be logged into Screwfix.com using the following email address snipped-for-privacy@XXXXX.co.uk. But Hurry! This voucher is only valid until Sunday 23rd June.
If you continue to have any problems or questions please let us know by emailing snipped-for-privacy@screwfix.com
Many thanks The Screwfix.com team