Not absolutely certain but I think the start date would be equivalent to spud date. The rig that begins a well isn't always the rig that finishes a well, that is, drills the well to total depth. It usually takes around 30 days to drill a XXL Bakken well to total depth. As for completing a well, from experience with wells of my own, the fracking/completion can come 2 months later or as much as 9 months later, depends on the operator. I hope this helps a little as there are no cut and dried answers.