Ahhhh, dang I thought you were superman, a masochist or both
Well you're going to want to intelligently increase the amount of cycling training you're doing as your tri season winds down. It's pretty typical for full time bike racers and especially stage racers to train on the bike 5 if not 6 days per week. Contrary to popular belief those don't necessarily have to be grueling long training rides. You can do an awful lot of quality training in hour and a half to three hour sessions if you focus on quality.
Some of your tri training base will cross over, but you're going to want more pure bike time prior to your event. And hopefully you either have previous race experience or you'll get in some one day races before your multi day event to work on tactics, group riding experience, bike handling in a fast pack, etc.
Check out Charles Howe's excellent guide to bike training based loosely on running principles from Lydiard/Daniels. You should already been well on the way to solid base from your tri season, but doing some additional SST (Sweet Spot Training) base building and then transitioning to more specific high end work before your events would make a lot of sense. Here's a link to his guide:
http://www.trainingsmartonline.com/images/Free_Triathlon_Articles/Power_Cycling_Training.pdf
Solid base and sustainable power are key for multi day events and you should have a head start there, but don't neglect bike racing specific high end work if your multi-day race includes circuit races, crits or other fast speedwork events.
Yeah, not exactly a cookie cutter workout plan, but multi day races really come down to basic fitness, depth of training base, ability to recover and good racing skills so you can race efficiently and not burn a lot of unecessary energy.
Good luck,
-Dave