Identical email to wife and me from related Plusnetter arrive hours apart

[#1]

it was sent to each of us, not to and cc. Message source details are identical, as proved by their side by side comparison in spreadsheet.

Yet mine arrived in my Inbox hours after hers.

How does something like that happen?

[#2]

When you say 'message source' do you mean that including the headers also? If so it's a client issue. What clients are you using? If the headers differ then that'll indicate where the relative hold up was, but won't necessarily explain why. 

[#3]

For clarity here it is, shortened and ammonised. Client is Thunderbird.

Moderator's note by Dick (Strat): Full quote of preceding post removed as per Forum rules.

[#4]

Did you forget to attach/include?

[#5]

@MJN Ooops, yes.

Return-path: <sender@sender.plus.com>

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To: "Wife" <wife@usplus.com>,

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Date: Mon, 4 Oct 2021 22:58:33 +0100

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[#6]

Were the headers of each received email exact the same? If so, that suggests they were indeed delivered at the same time which indeed you would expect given the common destination domain (and the fact they never even left Plusnet's infrastructure). If they appeared to arrive at different times I'd suspect the layer client stalling in some way, not checking for mail when expected to etc.