I've found out that there are the same console messages
L 07/29/2020 - 14:54:54: server_message: "quit"
L 07/29/2020 - 14:54:54: Log file closed
L 07/29/2020 - 14:54:54: server_message: "restart"
when a GSLT is used elsewhere and the server is shutting down therefore. But here this is not the case. As well there is no message that is telling about this problem as it would be when the server is shutting down therefore.
I think this might be related to GSLT. By the way this is only happening when the server is the changing map and not always.