From the link,
Although the FAA doesn’t go into detail, it seems the military is testing something that can disrupt GPS over a huge area, centered on China Lake, California, home of the Navy’s China Lake Naval Weapons Center. On Tuesday, June 7, the FAA is warning that GPS signals down to 50 feet AGL could be “unreliable or unavailable” between 9:30 a.m. and 3:30 p.m. local time over a radius of 253 nautical miles, which includes the L.A. Basin, Bay area and Las Vegas. There will be further outages of similar potential duration June 9, 21,23, 28 and 30. The circles expand with altitude and at 40,000 feet the interference will affect a circular area of the Southwest 950 nautical miles across, reaching central Oregon, Colorado and New Mexico.
This indicates the jamming is being done from the ground, not from the satellites. It is publicly known that new GPS satellites, block III(?) can jam signals in small areas several hundred kms across. Such a capability was not publicly known to be in older GPS satellites in operation during the Kargil conflict. Going over the symptoms described by one of BRF members experienced during his flying in the region, to me, it appeared that the mountainous terrain was masking signals causing outages/outliers.
Mountains can cause some satellites that are being tracked by the receiver to suddenly drop in/out of view. Unless the receiver software is designed to be robust against such interference, it can cause outliers, outages, even receiver reboots. Without proper tests being run with the receivers opened up for debugging, it simply cant be stated that 'US turned off GPS signals...'. Its merely a conjecture grounded in the general adverse feelings the US and Indian armed forces had for each other. There is absolutely no evidence to back such a conjecture.