OK, I'm getting a series of 'creepy' robocalls from a variety of numbers with the same prefix:  (303) 513-xxxx.  I've had calls from 303-513-4029 (this one), 303-513-7207, 303-513-3941, 303-513-1984, 303-5131769, 303-513-7188, and several others.  Oddly, they most often come in between 9-10 am.  What is 'creepy' is that - unlike many robocalls - these appear to be actual 'hijacked' numbers where the scammer is using the number of another person's active lines.  I did not answer the original call, so I called this number back (I am curious about this sometimes) and a woman answered and had no idea about a prior call (from 5 minutes ago). Is any one else getting calls from these types of numbers?