Transition from day to night or night to day DRASTICALLY degrades server FPS

I manage the BECTI Zerty 1.1.8 Seattle server and have noticed the following. Any time I start the clock at sunset the server FPS crawl down to 0 fps. During an Arma day the server can handle 40 people + AI and it sustains this at a solid 25 FPS. However, as soon as the sun starts to set (or rise) everything begins to slow down drastically (typically down to 0 server fps).

We ran fast time on an Arma 2 server and never had this problem.

Anyone having similar issues with other missions on Arma 3?

Had 36 players on today and checked the day/night and night/day transition. Before I changed the global time of the server, server FPS where at 20 fps. As soon as I set it to a time of 0530 or 1830ish (right around when the sun starts to set/rise and the lights are turning on/off) server FPS shot down to 8fps right away. As soon as I set it to 0000 or 1200 the server FPS jumped back to 20 fps. This was done with fast time off. Something weird is happening during the day/night transitions and it's crippling server FPS down to nothing.

I don't think this is a mission bug but something bigger.

Had 36 players on today and checked the day/night and night/day transition. Before I changed the global time of the server, server FPS where at 20 fps. As soon as I set it to a time of 0530 or 1830ish (right around when the sun starts to set/rise and the lights are turning on/off) server FPS shot down to 8fps right away. As soon as I set it to 0000 or 1200 the server FPS jumped back to 20 fps. This was done with fast time off. Something weird is happening during the day/night transitions and it's crippling server FPS down to nothing.

I don't think this is a mission bug but something bigger.

It migth be still a mission bug if some script interfere with the time of the mission, for examble the dynamic weather script. COuld you try to disactivate this one for another test?

It may also be generated by the number of AI in the server since they are updated each time there is a skiptime, in order to reevaluate they capcity to detect enemy unit with the current luminosity and so on.

Or maybe the server is wrongly doing some ligthning computation, which should not the case since it do not render anything.

Dynamic weather is disabled by default on the server (and was off during tests). As for the server AI, at the time I did the tests the game had gone on for 5 hours and 40 min and most towns had been capped by both teams (Town occupation is disabled by default, which means very few AI would be computed).

Tell me, what does NOT degrade your FPS in this crappy game?