Config parameter restart_game_year is located in the [NETWORK] section of the OPENTTD.cfg. The value set to this parameter represents the year the server will restart. If the value is set to zero (0) the game will run until it is manually reset. When set, the server will perform a restart on January 1st of value.
Minimum Value: 0
Maximum Value: 5,000,000
Not to be confused with Patch setting Ending Year which is only used for Single Player
This parameter replaces the previousely used restart_game_date.