It's only yesterday that particularly noticed it but I've had customers contacting me asking for copies - one in particular seems to have missed 8 out of the 10 I've sent them in the last couple of weeks.

It's reassuring that it's not just me but worrying that it's such a major issue and is taking so long to fix.

Strangely I've sent an email to a customer this morning and we always cc an internal email address but for that particular invoice I added my email address to the top line addresses.  It came through to me but not the cc address - the only difference between these accounts is the name before the @