I showed calculations to get to just under 300 awhile back in the thread. But the math is fairly simple. The rumor is 4500 pph, with 10 person cabins, that would be 450 cabins an hour. There are 3600 seconds per hour so you'd need to release a cabin every 8 seconds.
Assuming a line speed of 16 mph, you'd have a cabin spacing of 187.7 feet. Further assuming 6 miles exactly of cable, that would require 168 gondolas on cable.
There will be 8 full loading/unloading stations. If you give 90 seconds to load/unloaded you would need 11 gondolas per station, for 88 more. There will be a turn station that will probably have at least another 8 in it at a time. Then the handicap loops, of which there will be 6 will likely have ~3 or 4 at a time, so let's call that 21 more.
So we are at 168+88+8+22=285. There will likely be at least a few parked deducted to maintenance or as spares, so bump that up to right around 300.
Disclaimer, all numbers from memory. Obviously if the line speed is slower there will be more gondolas, if the line is a little longer there will be more to.