The Type-15 won't be anywhere near the T-90. Its only purpose there is fire support.
What Indians aren't yet understanding, is that their own armor is deployed
defensively. But the PLA (like all competent armies) only deploys heavy armor if it is planning to
maneuver aggressively. That's why the T-99s are in the back right now, and they will be forward deployed if/when needed. It's much easier for China to flood armor into a region like Depsang Plains quickly, than it would be for India because of simple geography alone, and that's not even counting the much better logistical infrastructure on the Chinese side.