This "Arma3" behavior was noticed, at least since last January, this year.
We believe that something was broken during an update along the way.
After a couple of "SAVE and EXIT" and "RESUME" of a multiplayer mission, the RESUMED waiting time for the mission to start becomes unbearable.
I've done a couple of obvious checks and one odd thing is that, most of the RESUME "waiting time", the HOST PC cpu is practically in idle state.
This was tested in "Windows 8.1 Pro" and "Windows 10" computer Hosts with the same results.
I'm aware that community MODs are not considered by Bohemia support but there's a detail that may help troubleshooting the problem: We were forced to stop using the "Task_Force_Radio" or "Task Force Arrowhead Radio (BETA)" or "ACRE2" MODs, because we've noticed that after the first multiplayer "SAVE and EXIT" and subsequent "RESUME", such radio MODs do not work as expected anymore.
We believe that the game "SAVE and EXIT" operation is ignoring MODs/scripts states and after RESUMING, such MODs stop working, yet, the MODS start to work again if instead of "RESUME" the host "RESTARTs" that same mission, also valid for the saved file size and RESUME waiting times (both become shorter).
In attach I'm sending the Eden Editor file, the multiplayer mission file PBO, 2 saved mission files folders (from 10 and 11 SET 2022) and the list of mods used to play the mission in html. {F2782226}