ErmengardeStopSniveling said: "Prices can rise and fall without notice. If there is not demand, the prices will drop.
The challenging part is that Felton's run coincides with one of the most lucrative time periods of the year (something that is probably deliberate on the part of the producers). If you were visiting New York in January, it might be a different story."
Rather surprisingly, Felton is moving a TON of tickets. By today's standard of generally weak advance sales, it's kind of eye-popping. I don't see discounts for Cursed Child happening this fall. Maybe none at all during his run.
That said, OP - there will definitely be discounts for Queen of Versailles, especially prior to opening, probably about a month out. Just hold out for a bit.