Question is, if Putin did start something - even small - qui bono? Who would benefit the most, Hillary or Trump? That might be playing in to Putin’s calculus also.
The problem with him starting something is the suspicion that obama might try to cancel the elections.
I doubt that Putin would take the chance, not knowing how the election will turn out.
It’s really only three weeks away and why wait until the last minute to warn your citizens to find the nearest bunker?
Better to have things well planned out. Avoids panic that way.