Looks like this may finally be happening. Per ESPN:

College football is taking steps toward establishing an early signing period, according to the NCAA official who manages the national letter of intent program.
Susan Peal, NCAA associate director of operations, said the continued acceleration of recruiting has led the Conference Commissioners Association to consider an earlier date to supplement the long-existing date in February, similar to the structure for basketball and other sports.

"I think everyone wants an early signing period," Peal said this week. "It's just trying to nail down what's the appropriate date for that."

Not sure that this will apply to traditional prep prospects right away. My intuition is that, if this is passed, they will first open it to JUCO kids and early enrollees, and perhaps wait a year or two before they extend it to the traditional prep prospects on schedule for a May graduation.