Ok ... then I must have misinterpret the first part (even if 11 LRIP birds was already assumed by late October), the 6 with the numbers however are new.
Concerning the 700+ I think that's more a bit of an overestimation ... just think about how many Flankers China has so far.
Deino
J-20 is going to be a force multiplier. Other than being a long range striker to take out the oil tankers, AWACS and EW planes, it could act as a commander to drones and 3rd and 4th generation fighters. When you see a cloud of j-10 J-11 and J-15, and J-16 in the sky on your radar screen coming at you, you know you are not going to defeat them with just your F-16, F-35, F-15, knowing lurking in them could be many J-20. Without enough F-22s to escort your other fighters, your battle plan is out of the window.
And if you just going to send F-22 to meet them, the J-1X fighters could act as a swarm of weapon platforms for the J-20, which provide them with targeting information. The J-20 will enable the J-1X fight better, so China might need less of them.
So in my opinion, 500 J-20 is minimum and even 800 of them is not too many. Remember, the USAF's original plan was to have 800 F-22s.
I might even say 1200, even 2000 J-20's is possible. I hear you doubters laughing and rolling on the floor and saying "NO, ITS IMPOSSIBLE! WHERE IS THE EVIDENCE? WHERE IS THE PROOF?"
But who is planning to build 2400 F-35 at a cost of $230 millions per plane, and has accumulated $20 Trillions national debt ($4 Trillions By George W. Bush, and $10 Trillions by Barry O'Bomber) and owes China $1.3 Trillion dollars.
And you think it is possible for China to build 1200-2000, or even just 500, J-20 at $120 millions per plane?