Ann: Southern Cooper Basin Operations Update,EWC-STX.AX, page-6

Moneytree,
my guess would be that they were approaching (or on) the gas type curve ramp up (critical desorption), and heading towards the commercial rate, but needed the quick shut-in the complete the K4 frac.
The frac of K4 would have been organised some time ago and I doubt they could just put it off for an unknown period in anticipation of a commercial flow rate. So they would have just proceeded to completion. It appears the wells were only shut in for 4 days which is good. If so then that is probably only 2-4 days to get back to where they were on that dewatering / depressuring anyway.
Then add K4 pumping into the mix (in the next few weeks) and that sucks more water away from K3 also.....therefore depressuring a greater area.
I still think K3 will be the well to achieve commerciality in the short term but obviously the frac of K4 has put that back a week or two probably. It sounds like the end result will be all the better for the extra productivity though.