According to the OP 6 eUpgrades is for flights less than 1,500 miles and 10 are required over 1,500 miles. This is the same as normal for T+ flights.

Not sure why anybody would do this when you can usually buy J class from ACV to these destinations for $300 return. That is an expensive use of eUpgrades!

I'm also not sure why ACV and AC call these Tango fares - last time I did one of these trips it was a "Tango" class but earned 100% miles.