May 22nd 2014, 9:19:19
The wiki is not wrong, but not right either. The Wiki GDI refers to how GDI works on clan servers, and the 18 hour rule is correct.
GDI works differently on solo servers.
Clan servers and Tournament server use GDI version A.
Primary and Express use GDI variant B.
Version A: Joining GDI, cannot have attacked last 18 hours. Countries in GDI cannot be attacked or attack countries that are more than twice, or less than half your NW. (Special attacks and harmful ops are allowed if in the 0.5-2x NW range.) That is, GDI is just a NW restriction. Declare War (an attack type on the War Page) can be used to ignore GDI on a target. You can leave GDI after a minimum duration.
For Tournament server, GDI is forced on all players; new countries start in GDI.
Version B: GDI does not restrict or change NW attack ranges in any way, unlike that of version A. Instead, GDI prevents other countries from using harmful spyops, and/or non-SS non-PS attacks on you, unless you have attacked them at least twice in the reset. That is, GDI is suicide protection. Once you perform a second attack (of any type) on the same country, that country (and only that country) can use any attack type on you, other than the default SS/PS. This is assymetric, you can't use any attack you want on him until he has also done at least 2 attacks on you in total, so the player that is on the receiving end of 2 attacks is said to have "first strike" initiative.
You must join GDI before attacking anyone in any way, or be disallowed permanently from joining GDI. After joining GDI, you may not leave it.
The Declare War attack type does not exist on Primary/Express.