Email Alerts from the router for a dropped connection/reconnect show the correct time and year but the incorrect MONTH in the email client (Thunderbird); the month is advanced by one, for example, at the time of posting it is July, the 7th month, yet email displays as the 8th month.

I have checked what I considered obvious causes: ntp server, mail alert settings, time zone etc and all appear correct.

I don't believe, logically, it can be the email provider (gmail): I have multiple daily emails from other sources/devices and only the Draytek email exhibits this problem.

Ideas anyone?

Silly question I know but given the date on which you are posting this, is it possible that it's using US format - i.e. mixing up day and month 7/8 ?

Not a totally daft reply, however, this has been happening for several months on different dates.....and if it was US format I can't find anywhere in router settings where it is not set to "UK", "GMT" and, as I said, unlikely, to be gmail/google settings wrong as this is the only email coming into the account showing this problem.