(...)
If 1 trillion diff corresponds to $42k price for BTC, what BTC price of $110 corresponds to which diff?
That should give us the end-point of difficulty leveling off and should also tell us roughly when to expect that to finish levelling.
≃2.6 billion diff = ways to go.
That'll take about 14 difficulty adjustments at 30% each. I think we'll reach that by end of this year.