"Defence" and "base" infantry divisions

[Solaristics]

Playing the 1942 scenario, I see "defence" and "base" infantry divisions on the map for the Japanese (they have a coastal gun icon). Is it possible to build these? I thought the coastal defence item in the support build menu were them, since they have the same symbol, but they are hex assets.

[eskuche]

These AFAIK are special defense units with a separate set of base stats (including ops points). You cannot build them. I guess their advancements proceed as per their offensive counterparts.

[AlvaroSousa]

Basically it is fixed garrisons with permanent coastal gun placements.

Their size isn't viable to be made into a constructed unit. Then you have the guns that were there already. It would be an exploitable unit. So they are just there to be there as a little flavor and defense.