I'll be cautiously optimistic about these for now. Unless an official announcement about Team Plasma is going to be made soon, I do find it a little hard to believe that such a major turn of events would be revealed in such a way. I would rather wait until we hear a little more before I get my hopes up too high.
The Pierce comment is interesting because it implies Giovanni really did only pull his forces out of Unova temporarily. I get the feeling that if there actually is going to be a Team Plasma arc at Dragonspiral Tower, the upcoming Tirtouga arc might be a stage-setter for it and Giovanni could be planning to make his move to get the Light Stone first.
Did Iwane not say anything about the banned episodes? I would think that if we were only a couple months off of Team Plasma they would have to air soon first.
All projects cancelled. Goodbye.