Rev5 May Knox to IMKY August...Enough Tiime to Train for Full?

I'm planning on doing the Rev3 May Knox 1/2 next year and was wondering if I would have enough time to train up for the full at KY?  I don't want to overtrain for the 1/2 and want to consider both races as my A race...vs using the 1/2 as a training race.  My swim endurance will be fine by the 1/2 to be able to do the full in August.  My run should be fine, because I can maintain the long distance runs and get in a few 20s for the full. My concern is the bike.  For the 1/2, I only plan to peak at 1 or 2 x 75 milers for my long bike ride and was worried that I would not have enough time for KY.  Also, this will be my first 1/2 Iron and first Full Iron.  I've done a few marathons in the past and know how to plan for these.  Since I'm still new to Tris, I was originially thinking of just using 2011 as 1/2 Iron year...May Rev and Sept Augusta and focusing on building speed, then in 2012 go for a full Iron.   However, I didn't know if it was worth it to go from May to August and build upon the training or set out a full year to train for a full Iron.  My goal is to finish well and not just to finish... Any thoughts?