Static Mode and Construction Units

[Medicusa]

2 things:
I never tried it but I wonder if it is a good idea to cycle front units out after they are tired, lost CPP and need refits and put them into static mode 0-3 hexes from a depot. This way I should have more vehicle for my other units, safe fuel and get faster these units ready. But, this cost admin points, dont it? Is it worth it?

How exactly do construction units work? I mean not the rail repair. All the other construction units repair stuff in cities or help build fort level faster, right? Is it enough to have them in a 5 star HQ so they get teleported where needed or should I assign them even to regiments?
My impression so far is, there are so many of these construction units that I never know what to do with them. So I was thinking, could I place them into regiments to help them fortify faster certain fronts to have more combat units at important fronts?

[Bamilus]

1) I havent fiddled with it but i dont think static should be used for refitting purposes. Its really only for units that wont move for a long time. Its much better just to move them a hex away from front line and if you dont have enough units to do that then you use breakdown to split into regiments and cycle that way.

2) Correct, non rail construction units dont show up on map visually but they are allocated within command range to cities that have damaged facilities. I believe in chapter on ground units (22?) It lists the descending priority of how the AI assigns the units (within command range). Similar to rail support units, if you want a specific area to be prioritized you should move construction units to corps level as its command range is 5 so it will only do 5 hexes out from that. If you leave them all in AG level or OKH, they might work on things you dont feel they should be, because they have a large command range and so there's more targets for them to pick.

Also, some level of repair happens every turn organically even without construction units. Also, for 1AP each you can A) initiate a priority repair on a facility, which tells the AI to assign a construction unit to it next turn and to stay there until that facility is complete or B) manually attach a construction unit to a city which means it will stay there until EVERYTHING is repaired. I never use B and only use A as I typically want construction units to focus on railyards (manpower is fine being repaired slowly over time). I don't know if its optimal, but especially early game every level 2+ railyard I capture get's priority repaired initiated same turn so I know they will focus on fixing those first, since the 2+ railyards add extra capacity.