I don’t know about mid season adjustments in Year 2, but Rhule made some off season schematic adjustments between Years 2 and 3 at both Temple and Baylor that appear to be critical for their Year 3 success.
At Temple the offensive approach was adjusted after they were initially trying to be more of a spread team. Rhule even proclaimed "We're going to throw the ball until we become good at it." By the end of Year 2, he was frustrated that they weren’t able to successfully run the ball when they felt they needed to (sounds very familiar). They averaged 107.8 rushing yards a game with 11 rushing TDs in 12 games that season. So they changed their approach. The result was averaging 149.8 rushing yards and 25 rushing TDs in Year 3 (24 rushing TDs in the regular season, discounting the AAC championship game and bowl game) and 176.4 rushing yards with 31 rushing TDs in Year 4 (29 rushing TDs in the regular season).
Satterfield still called the plays in Year 3, but moved from coaching QBs to RBs. Glenn Thomas was also hired that year as QB coach. Tyree Foreman, the previous RB coach, left to go coach at Tennessee Tech (not sure if he was fired, encouraged to move on, or made the decision on his own). Adam DiMichele, who took over WRs in 2014* was made Director of Player Development while Frisman Jackson was hired from NC State to coach WRs. Essentially every offensive position except for TEs and OL had a new position coach between Rhule's Year 2 and Year 3 to go along with a new offensive approach to was supposed to be more physical.
After 2018, Baylor changed their defensive scheme from a 4-3 to a 3-3-5. Some credit this scheme approach for being a major part of their success that year. The only staff adjustment was bringing in Satterfield to coach TEs and free up Joey McGuire to coach DEs. An article discussing the scheme change can be found here:
https://sportstreatise.com/2019/07/rhules-plan-to-save-the-defense/
This quote from Rhule in particular when discussing the change before the 2019 season even started gives me some hope that Rhule doesn't just have his head in the sand on noting his teams' deficiencies:
"I just think after going through the conference last year when we went back and watched our cut-ups, and when we were in that 3-down stuff, um, Clay Johnston had elite games, we eliminated the explosive plays, we had a little more speed on the field so we’ve just kinda flipped it. We’re still going to do both but instead of being based out of the 4-3 and mixing in some 3-down stuff, I just think that Phil has said, let’s base out of the 3-down and then we always have the ability to put the 4th rusher in and get after the QB."
It sounds like a coach who is adaptable, even if we feel he has been as stubborn as can be in some ways this year.
The jump made from Year 2 to Year 3 wasn't necessarily done in a vacuum where Rhule just kept doing the same thing until it worked. Granted, it does seem like he is committed to whatever approach he decides on while the season is going. But come post-season time, he has a history of reflecting and adjusting.
* In 2013 Rhule hired Terry M Smith, who was a highschool football head coach in Pennsylvania. This seems to be the prototype of Rhule's MO of hiring highschool head coaches. Smith coached for a year before leaving to coach DBs at Penn State for James Franklin. Smith is still there as Franklin's Associate Head Coach now.