Though this also means that Karl Anderson, Luke Gallows, and Shinsuke Nakamura likely also have expiring contracts in early 2019. It is clear at this point that only AJ is being negotiated with by the company or at least that is only person who sites are reporting is being negotiated with. At this point it is almost definite that Styles will remain with the WWE, but his contract will be a little different this time around. This time AJ will have the chance to appear at less house show's similar to Randy Orton's contract this way AJ could have more time with his family which is something that he wants according to news reports.
Overall I do think that AJ still has a few years left in the WWE before he will hang up the boots for good and that means I think a few more dream matches can happen and maybe even some more title reigns. Either way the future for AJ Styles is still very bright in the WWE for the near future. As for his former New Japan cohorts I am not to sure what there futures may hold as far as there place in the WWE.