Date header, Individual.net, slrn, & Arch linux

[Whiskers]

A recent thread in news.software.readers has caused me to take notice of
the headers appearing for my own posts, and I notice that although my
software provides a Date header that looks like this

Date: Mon, 4 Jul 2016 12:07:42 +0100

as is recorded locally in my ~/News/Posts file which is generated by
slrn, before or at the same time as they are posted to Individual.net,
when I fetch my articles from the server the Date header has been
transformed into this form

Date: 4 Jul 2016 11:07:42 GMT

which although it represents the same moment in time, is not what I
posted and indicates the wrong time zone for me (which is currently
"BST" in that obsolete format).

I believe it is wrong for a news-server to change a valid Date header
(or anything else) posted by a user.

Looking at old posts, I think this misconduct began at some time around
the end of November and start of December 2015. Which shows how much
attention I pay to my own headers.

So, has anyone got a clue as to what happened around that time and what
needs to be done to correct it and by whom? I'm quite prepared to
accept that there is something about my system or software that is
'wrong' but I can't work out what it might be. It /looks/ as though the
fault lies with Individual.net.

For the record,

~]$ timedatectl
Local time: Mon 2016-07-04 13:55:30 BST
Universal time: Mon 2016-07-04 12:55:30 UTC
RTC time: Mon 2016-07-04 12:55:30
Time zone: Europe/London (BST, +0100)
Network time on: yes
NTP synchronized: yes
RTC in local TZ: no
~]$

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-- ^^^^^^^^^^
-- Whiskers
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