Hi, @sover steve
Thank you for posting in Microsoft Q&A forum.
No, we cannot directly backup from version 2303 and restore to version 2403 of Configuration Manager. Before restoring the backup, we must install the same version of Configuration Manager that was running when the backup was created.
Therefore, you may first upgrade version 2303 to 2403 on the old server, then backup it, and then restore to version 2403 on the new server.
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