Combat engineers can squeeze in fort reduction under any odds.
Japan has very few true independent combat engineer units, and to my knowledge none of them start in China. As a matter of fact throughout '42 there are exactly three that I can think of and two of them are only company sized. She does have a few independent engineer regiments which have roughly 16 IJA engineer devices 'attached', but these are TO&E additions and once eliminated they're not replaced.
I've never seen a fort reduction by way of engineers integrated within combat units, only through odds levels. At least through a deliberate attack. Shock attacks are a different matter. Not that I suggest LST should shock attack as the odds and fort levels are not in his favor. Talk about a massacre.[:-]
