Paul wrote (2021-02-02):

 PQ> Hi! Oli,

 PQ> On 02 Feb 2021, Oli said the following...

 Ol>> @TZUTC: 0100

 PQ>>> How's mine?  (I'll see after it's sent...)

 Ol>> Looks good, your mail is not from the future. Time is displayed as
 Ol>> 08:43 (my local time is 08:54).

 PQ> Yes.  It's displaying your local time for when I launched the note at my
 PQ> end. It was 17:43 AEST here.  Your 9 hour difference shows.

I know, I intentionally set my mail client to use local time in the message
list.
The message itself shows your local time and TZ.

Date: Tue, 2 Feb 2021 18:30:33 +1000
X-JAM-FTSKLUDGE: TZUTC: 1000

 PQ> Apologies if I'm telling you something already known to you.

Apologies accepted ;-)
(I mean no apologies needed)

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