8-10 weeks of reduced volume is what I do. You might need more or less time depending on how demanding your schedule was. And don't take the time totally off, just cut it back a bit (say 33-50%) and don't stress about it - if you don't want to ride, don't! If you want to stay in bed, do it!
edit: another thing to consider is how long your season is. In socal we race (road) from Feb through August, and track goes for nearly 2 months after that, although I typically stop racing all together by August.
If the cross scene in your area doesn't start till winter, you can afford a bigger break. As long as you keep some baseline bike fitness it shouldn't take more than 3 months of dedicated training to get back into fighting shape.
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"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
Last edited by TMonk; 11-21-17 at 02:34 PM.