The supply lines for the army are unlikely to become under attack by India unless PLA's air defences and PLAAF get neutralised by IAF. However, the PLA has gradually moved a fairly large volume of military equipment and troops to reinforce this region. It may still be lower in number to deployable IA equivalents but the gap isn't anywhere near as large as it used to be. Sure IA have closer supply lines but fewer equipment overall.
Any actual war happening here would be pretty high intensity and probably will rest entirely on the effectiveness of respective airforces. Air superiority and SEAD+DEAD means bombers and attack aircraft along with UAVs, will have free reign, pretty much negating any one sided ground force numerical superiority. When it comes to bombers, strike aircraft, and UAVs for air to ground, India is at a significant disadvantage. It will need to use its airforce to defeat the PLAAF stationed near this region and suppress PLA's air defences. No doubt IA has the numbers to hold back any PLA advance (unless PLA matches the IA) but PLA and PLARF will be doing their part in attacking IAF on the ground using long ranged artillery, cruise missiles, and ballistic missiles. Once airfields are actually damaged, they aren't that easy to get back into service condition. This may be more than enough to help the PLAAF offset the numerical advantage of IAF.
Well your G 219 is not too far away and once your airfield are neutralized , Tibet is up for grab. So your supply lines are pretty much vulnerable.
As for PLAAF goes, they might have numerical superiority over all but it;s the man and tactics behind these machines which won war. Chinese pilots & their tactics have been exposed multiple times in various exercises and lack the practical war experience. Remember the war exercises that China had with Malaysia... your fighters were bunnies for Malaysia air force.
FYI - your most stealth fighter was tracked and recorded by Our fighters some 100 KM's away from LAC ...