To be grounded you have to have actual lifted off...Grounded actually
Whether or not this is true, im not sure, but remeber that most missiles are not launched at max range. With KLJ-7V2's 150km range, the block 2 can still use the PL-15 very effective, and at at least 50 km out further than SD-10. But more than that range, it can more effectively use the weapon due to its larger no escape zone. If the SD-10A and AIM-120C5 have NEZ of ~40-45km (which is where most BVR engagements likely occur), the PL-15 may have an NEZ of 60-85km+. This will enable even a JF-17 blk2 to effectively take out aircraft further than they can even reach the JF-17 without their NEZ (in R-77 or MICA case). So it will still be very helpful for blk 2.100 PL15s were widely reported to have been sent over post Pulwama encounter. So I would contest that. However to what extent will the JFT block 2 radar be able to guide the PL15 to its target remains to be seen.