Sadly, I didn't pick it up until this afternoon, so I replied pointing out that leaving it till after 7pm is a bit late for a same day appointment, and asking that if he's emailing for a same-day meeting it's better to do so before about 3pm, or to contact me by text before 5pm.
My reply bounced back because it's an O2 account (presumably he used his mobile phone to email) and his inbox is full. Aaaargh!
So somewhere out there, is a punter complaining that WGs don't answer their emails...