Slow iCloud Email Delivery

While iCloud email message delivery is most often very quick (a few seconds), it sometimes takes 4-10 minutes, such as:

Received: from o**********v.icloud.com (localhost [127.0.0.1]) by o***********v.icloud.com (Postfix) with ESMTPS id 64DA918009E1 for <c*************7@gmail.com>; Thu,

  5 Jun 2025 16:45:12 +0000 (UTC)

Received: from p00-mailws2-67fc69d965-69hht (pv48p65ic-bookmarkdavdbvip001.me.com [10.112.64.97]) by o********v.icloud.com (Postfix) with ESMTPSA id 36D2318009F5 for <c**********7@gmail.com>; Thu,

  5 Jun 2025 16:40:42 +0000 (UTC)

Is that normal?

Used both iCloud Mail in Safari and the iPadOS Mail app.

"Undo send delay" is off.

iPadOS 18.5

[Edited by Moderator]