Retire after Two Years, Instead of Three:

Some of Air Force Reserve Command’s lieutenant colonels and colonels can now retire after spending two years time-in-grade, rather than the customary three years. As part of its force shaping efforts, the Air Force has reduced the time-in-grade requirement from three years to two for no more than two percent of a grade’s authorized end strength each year. That means a maximum of 126 lieutenant colonels and 30 colonels are eligible to retire in 2007.