I think Gus 1 was incredibly formative for Jones. Jones fought tall and lanky guys on his rise up, but nothing quite like Gus. Gus had the hands, footwork, and TDD to cause legit problems for Jones. Whether Jones trained appropriately or not, Jones had issues.
However, Jones made the changes in the second fight. Hampered Gus' movement with kicks, utilized the clinch more, feinted TDs, kept his distance, and let Gus do the chasing. So, in theory, Jones has an answer.
What can Reyes do to succeed? Circle, cut-off, and use technical striking. He'd have to pressure, but he'd also gotta be wary of the clinch, and his lead leg among other things like the the TDs. Reyes doesn't have the speed or volume of Gus, but he definitely hits harder and uses kicks more.
He's not as unpredictable or explosive as Walker, so he might not give Jones too much to think about, which may be an issue because Jon usually out thinks and outworks his opponents, and I believe fighters have to prepare for the mind and intangibles of Jones, not just what they see on first impression.
For example, Glover was a very heavy hitter. Jon hadn't fought one of those in awhile at the time. Jon used the clinch to lock up Glover's arm to hyperextend it. All of Glover's power shots did little damage to Jones as he worn on and beat Glover up in the phone booth. It was just one of those things that became a factor early on, but didn't pay off until later in the rounds. Kinda like investing in the body, not just to tire out the opponent, but to condition their responses so that an attack high while feinted low lands on the face.
This is what Reyes and other contenders have to prepare for.