I think there is a possibility, but there is also now a low probability. I think the window is still open for WAC football, but it is closing. It would probably be a conference of convenience at least temporarily. Still seems like it would have been advantageous for the WAC to maintain the ability to sponsor FBS football even if they had to use eastern and mid-western universities to do it. It would be understood that a lot of the universities would use the WAC as a stepping stone, but it would also keep WAC football viable when the western universities got ready to make the jump. Something similar happened when the Sun Belt started football. Football members included Utah State (2 years), Idaho (4 years), and New Mexico State (5 years). Each moved on as openings in western conferences opened up. Until New Mexico State and Idaho were invited back as associate members last year, the Sun Belt built its membership in a fairly tight geographic footprint.

Depending on impacts of the proposed DI split version 2.0, there may be pressures on some FCS universities to move up. With the Sun Belt as the only game in town with a limited number of tickets available, the WAC could be holding a pretty good ticket for some programs thinking outside of the box.

Based on what I have seen, I think the following are or have been contemplating a move up to FBS.

FCS Rating Division I Rating
Jacksonville State 29 137
Liberty University 37 148
Eastern Kentucky 49 165
Lamar 85 209
Sam Houston State 6 76
Missouri State 56 174
James Madison - probably will move up without WAC-E

If Lamar and SHSU moved, McNeese might go along.
McNeese 5 75

That set up would make up an Eastern Division of a future conference with a footprint similar to the current or speculated Sun Belt.

It could turn into a pretty good arrangement if some of the western and mid-western universities later came in to form a Western Division.
FCS Rating Division I Rating
North Dakota State 1 24
North Dakota 77 200
South Dakota 59 179
South Dakota State 24 130
Montana State 17 116
Montana 19 118

Compare the above with the current Sun Belt rankings

Current Sun Belt Division Ranking
W Kentucky (to CUSA) 70

ULL 79
Texas State 98
South Alabama 106
Arkansas State 110
Troy 112
ULM 121
Ga State 204

SBC Entering
Appalachian State 195
Georgia Southern 147
New Mexico State 222
Idaho 166