Over 3000 wells to be completed still. I don't think they can finish them all before this time next year.
They likely won't. One well on the lease is enough to hold by production. Up here, it is not uncommon to have another three to seven wells in different parts of the target zones spread out across the width of the rectangle (1280 acre/2 section spacing), usually two to four in the Three Forks, two to four in the Middle Bakken, sometimes additional wells in the second zone in the Three Forks, and sometimes (when present) wells in the Pronghorn (a unit between the lower Bakken Shale and the Top of the Three Forks that isn't as universally present in the Basin).
It is cheaper to drill them while the rig is moved in and set up, and let the additional wells wait for better economics to frac them. In the event that prices shifted suddenly, the 'fraclog' (backlog of completion work) would likely get longer, not shorter, as drilling resumed, but in the event of a slower price recovery, it may be that those wells would be fracced before additional wells were drilled. Some operators may just be waiting from frac costs to drop as competition makes the market for services more cutthroat, but the inventory of DUC wells may keep that from being as much a drop as they would like. Others may be waiting on infrastructure or takeaway capacity which is cheaper to ship crude on (pipelines, for instance).
I would expect similar market driven factors affecting the DUC wells in other areas like the Permian Basin, Marcellus, Utica, and the Haynesville, for instance, and similar rationales affecting the completion of those wells.