Because the OP has a UK e-mail address, and I'm not sure anyone
outside the US thinks of Sunday as the 1st day of the week. That is, I
was guessing the OP would find it more obvious to think of Thursday as
the 4th day of the week.


Don't know if that is true for UK, in Sweden the week starts with Monday,
another thing is that it is easier for instance to use as a criteria e.g.


=WEEKDAY(A1,2)<6

is simpler than

=AND(WEEKDAY(A1)1,WEEKDAY(A1)<7)


--
Regards,

Peo Sjoblom