Theoratically it can go, but practically PAF hasnt pushed any JF-17 to beyond 1 mach. Can be multiple resaons, one being the stress on the aluminum frames and resultant considerable decrease in JF-17 airframe life considerably which Indian newspaper reported also
Consider this news of Indian newspaper, the amount of hacking they have done, it was expected they will leak such news
There are problems with the fuselage, with cracks being detected in the lower fairing skin. This is an area that is most affected by G or gravity-related pressures.
www.timesnownews.com
P.S Just before someone attack Indian source, German refusing engines for Pakistani subs was first reported by Indian newspapers. They are hacking PAC, MoF, and dozens of others government institutions. There was a hacker on Twitter who used to share Pakistani Army documents and images which he hacked. This week some hacker got into webex session of IMF and Pakistani MoF delegation.