"We're definitely going to hold him until we get to the bottom of this," coach Bill Self said Thursday, a day before the Jayhawks play South Dakota State.
Preston was held out of Tuesday's win over No. 7 Kentucky in Chicago after the university's compliance department sought to get a "clearer financial picture" following a single-car incident involving him on Saturday. The school said Preston's car hit a curb, causing minor damage to the tires. No police report was filed.
The incident left enough questions that Self decided to keep Preston out of the Kentucky game not long before tipoff. Preston also missed the opener against Tennessee State after missing curfew and failing to attend classes the following day.
Asked who the car Preston was driving was registered to, Self couldn't provide an answer.
"I can't comment on any of that stuff, but when we have a resolution to it we'll be sure to let everybody know," Self said Thursday.
The timetable for Preston's return was unclear. Self acknowledged that there is some complexity to the situation but said he believes it will be settled soon.
Self said he hasn't seen Preston since the team returned from Chicago as the Jayhawks didn't practice yesterday, but Self added that the forward has been "very positive" when communicating via text.
If Preston is unable to go against the Jackrabbits, the Jayhawks will once again have to work with the almost nonexistent depth they had against Kentucky. Only seven scholarship players were available, and just two were part of the frontcourt.
"We've got to prepare like we're not going to have him," Self said. "And then it would be a bonus if you did. But we'll certainly prepare like we're not going to."
Preston was ranked No. 18 in the 2017 ESPN 100 and was expected to be a key contributor to a team that is lacking in frontcourt depth.
The Associated Press contributed to this report.