Regarding AJ Styles leaving TNA, it is not part of the storyline that they began a few months ago. Things could change between now and December 16th but Styles is indeed leaving TNA if they don't.
Styles is currently taking independent bookings and word is that he's asking between $3,000 and $4,000 per appearance. It was noted that Styles' scheduled Q&A tour of the UK was pushed back due to a Diamond Dallas Page tour taking place around the same time but another reason for the delay is that TNA's lawyers sent legal letters to the promoters to make sure they weren't infringing on anything TNA owns rights to.
The main problem between TNA and AJ is money. TNA simply would not give him what he wanted. Now there's a feeling within TNA, with so many contracts coming up in the next year, that a lot of guys are going to end up singing deals for less than they were previously making just to keep their jobs. The feeling is if TNA wouldn't give AJ Styles more money, then they probably won't be giving any one else more money.