Not positive on the wide bodies, but, SWA has stated that they will half to look at larger planes sometime in the future. Don't connect that directly with the current rumors, as SWA has also considered looking at the new Max 10 as a larger aircraft. I see a possible 2nd story happening over in Hawaii. It could end up that SWA might get enough passengers from Hawaii as well as other airlines, and Hawaii might wanna call in a favor to SWA with an agreement of some sort with a possibility of a merger later on.
My guess now has more leaned towards the announcement coming will be about Southwest starting flights to Hawaii as this article below tells that they have some pretty good info that that will be what it is and they are a news agency from Hawaii called Hawaii News Now--not HNN from here called Headline News Network. I kind of put a little more weight with them as they are from over there and have better access to the Hawaiian gov. for info. We will see. I am being greedy here robbed, I wanna see flights start to Hawaii on SWA before end of this year, but not sure if it's enough time. At latest I am hoping for early 2018 and hopefully not later than mid 2018.
Here's that Hawaiian news article below, take note of the highlighted 2nd or 3rd paragraph where they say they have real good evidence. This is the part that got me more excited:
Seeking Alpha, a crowd-sourced financial analysis company,
reported Monday that they had uncovered documents between Southwest and the Hawaii government that made the carrier's entry into the Hawaiian market a surety.
Speculation ramps up as Southwest plays down potential Hawaii routes