I see the testing of 102 is in full effect.
Although my experiences with buid 101 on this issue might be needless info by now,
I still would like to take my chances it is not. (short version, last paragraph)
Note:
Always used Formula Masters mod in these examples.
I used to race with 15+ drivers on these servers mentioned many times, they're capable.
A few days ago I ran into a hotstreak with this bug.
There were around 9-15 drivers each time.
I can say with certainty, that two races started with 11 drivers.
Right after the green lights we all start dissapearing, drivers warping all around etc.
Every race only 3-6 drivers make the second lap. People disconnect by numbers.
Some say they disconnected, others just left thinking the server/connection was bad.
I can't confirm the disconnecting as it never happened to me.
In qualifying there was none of this, but noticable lag jerks. Not constantly but one or two times a lap, with consistency.
I don't know if it's related to this bug, but I also have a lot of weird things going on with statuses in this build:
Race Length
A few guys, including me, were waiting to join as the race was still going on.
It was a 10 laps race, but to all of the waiting people it showed they were racing in their 11/10 lap with status 110%.
The race ended after lap 12/10 120% in our screens.
We didn't have confirmation on this from the people driving at the moment, but it was clear after joining that they were running 10 laps races.
Status Bar
The bar which shows the cars and their relative position on track, it was more wrong then normal.
Drivers showing as in pit, while they actually were driving on track.
(happened in every session)
Timesheet colors
With a couple of guys I was doing a 50+ lap practise/setup session.
People were joining now and then but never more then 8 drivers in the room.
As with the status bar, the drivers current status on the time monitor was often not correct.
(green ontrack, blue pits, white pitbox).
When I was chatting with another guy for a while it even began to show me as blue, leaving pitbox.
The same for the other driver who was clearly not driving.
Maybe I haven't paid closer attention to this in earlier builds, but I think this was always correct.
In short, I experienced this lag in races with 10+ drivers.
When we were with less than 10 drivers it was a lot less apparent. Never had it with 6- drivers.
But, regardless of number of drivers, there always is consistent lag. One, two or three times a lap a short lag jerk.
One time more noticable then the other. And statuses seem affected somehow.
That's what I got for now.
I hope further tests will shine more light on this!