Last record I can find of CFF using 01 was back in 2006 by Jack Teague. Car was white/blue and he ran the 2nd and last race of the year.
Curiously, in 2006, the only group that seemed to know what went in the "MAKE" (of car) box at Race 13 was Group 2 drivers. Everybody else who entered said they were driving cars made by "ICSCC", "IRDC", "CACC" or "SCCA".
In Conference we do not give the previous year's champion a special car number. Car number equals licence number. Since we have multiple classes running in every group, giving the class champion the "01" could end up with several "01" cars running at the same time. The result would be competitors and folks in T&S.