Simple. By the time HCJG is axed, most schools will have completed their recruiting for next year. If he wants to fully explore his options, the time is now, not much later
Schools will have a scholarship ready, actually more scholarships available in the Spring than late fall (now) for someone like Tilmon. Not only will the available options include all schools that will carry a scholarship into Spring, but you will add all NBA defections, transfers, and spots that will open due to coaches having the input/experience of the current seasons. Schools will make scholarship available for Tilmon, so not an issue.