@zhanghm18 It shouldn't be building fewer of them - to clarify, the change I mentioned in the summary was to reduce how threatening M28 thinks its Czars and soulrippers are when judging if it's got a strong enough air force to assault a heavily fortified position. I was finding that it would proceed with an assault (as a Czar in mass terms is c.26 broadswords), the czar would quickly lose its shield, and it would retreat before it had overwhelmed the shields, leading to a bunch of losses for no gain.
The reason it doesnt build them much though is both that it currently handles/uses them similarly to a normal gunship (M27's logic for czar in particular was highly specialised and would take some time to put in place) and I'm concerned that mass for mass T3 gunships (restorers/wailers) would be more cost effective since M28 is able to significantly reduce the downside of mass T3 gunships (that they die easily to aoe) while benefiting more from the upside (can be repaired at air staging).