Thanks for your reply Murphwiz.
As you say, most garages/factors, etc., work on next day delivery for those kind of parts and it should be no different for a major, well known, garage. Worse case scenario ... if there had of been a lead time issue from date of delivery of the part, the garage should have communicated this to the customer (in my opinion) so that the customer could have organised alternative transport, etc., and whom I think would have been better satisfied knowing what was going on.
I hope it's better next time for the customer, although they are probably hoping there isn't a next time!
Thanks again
Fiona