shimano

I'm interested in doing my first Brevet's this spring and would like some advice on how others train during the off season to help them maintain their miles and endurance during the off season. Currently, I do weight training, swimming,other cross training cardio exercises such as running, and classes at my local health club. Does anyone follow a regimen during the off season that has helped them prepare for the start of a new season? When is the best time to get back on the bike and how should I go about building my mileage so I'm ready? I want to make sure that I build my mileage gradually without overtraining. Any thoughts and suggestions would be helpful.

I live in Chicago.

Thanks,
Tom