Not on the 64GB configuration but I believe $300-400 off is possible on higher end configurations (e.g. 1TB WiFi MSRP $1550/1750, LTE MSRP: $1700/1900). Moreso if Apple actually releases new models and adjusts pricing on the storage tiers.You’re not going to find $400 off an iPad during Black Friday ... I also never said you have to buy one now. I been saying IF there is a good deal on one then go buy it. This waiting game is nonsense because you can say hmm it’s a spec upgrade I can wait another year. If you need an iPad go buy one ... if you don’t then don’t.
Iirc, places like Best Buy, Amazon and Walmart, have already offered $200-350 off higher end Pro configurations in past sales.
Besides, iPad Pro release dates have been all over the place thus far so I wouldn't rely on them being a good guide.
2015
Nov: iPad Pro 12.9 A9X 4GB
2016
Mar: iPad Pro 9.7 A9X 2GB (+ 256GB Pro 12.9)
2017
Jun: iPad Pro 12.9 & 10.5 A10X 4GB
2018
Oct: iPad Pro 12.9 & 11 A11X 4-6GB
My only takeaway from the above is that Apple will release new iPad Pros when they're ready. Sure, it's possible there won't be new models until 2020. If someone's not in an absolute hurry to upgrade though, at this point in time, it's worth waiting until the upcoming keynote next month to see if anything shakes out (both in terms of Pro and the rumored 10.2" iPad).