grand_campaign_update_war_participants_effect

grand_campaign_update_war_participants_effect = {
	#bring in all relevant defenders
	scope:target_title ?= {
		every_in_de_jure_hierarchy = {
			holder ?= {
				if = {
					limit = {
						NOR = {
							government_allows = redirects_wars_to_overlord
							top_overlord = scope:owner
							any_character_war = {
								this = scope:grand_campaign_war
							}
						}
					}
					scope:grand_campaign_war ?= {
						add_defender = prev
					}
				}
			}
		}
	}
	scope:great_project = {
		every_contribution = {
			limit = {
				contribution_is_funded = yes
			}
			contributor = {
				if = {
					limit = {
						this != scope:war_leader
						this != scope:owner
						NOT = {
							any_character_war = {
								scope:grand_campaign_war ?= this
							}
						}
					}
					save_scope_as = contributor
					trigger_event = tgp_china_ministry.0004
				}
			}
		}
	}
}

As written in game/common/scripted_effects/10_dlc_tgp_scripted_effects.txt.