What's the restrictions on mid decade redistricting if any?
Tbh not sure, if they draw a 10-4 in the beginning maybe they won't take the move of mid decade redistricting for 1 congressional seat that slightly weakens others. If there aren't any restrictions but the D court imposes some 6D map or something I would expect them to do it.
A mid decade redraw would be illegal for the state legislative maps unless court-ordered, but there are no restrictions for redrawing the congressional map mid decade.
Is there a window as to where maps for Congress can be drawn without being subject to veto? After a certain date, would the maps be subject to veto?
There is no veto on maps period because until the 1980's/early 1990s, there was no veto at all in NC for the Governor. This was because after the 1890s, it was seen as plausible for Republicans to get the Governorship, but highly unlikely to ever flip the legislature.
In the 1980s, Reagan had carried a Republican into the Governorship and though they decided to create the veto power for the first time under this state's constitution, it did not apply to redistricting maps at all.
That is partially why NC Republicans felt so embolden to strip power from the Governor as this state has a long tradition of legislative supremacy and a weak Governor.