Alp Arslan custom campaign

Currently playing the custom campaign Alp Arslan and just finished the 4th mission. Is there a design flaw in this mission? I ask only because I won via a relic victory!?! Early on I saw 4 relics grouped together and gathered them in. Much to my surprise the countdown started. After a half hour victory was declared, notwithstanding that none of the enemies were defeated. Easiest win I’ve ever had, but I wonder if this is what the author of the game intended.