Oh, you should be fine! Sounds like you have a good running and cycling base under you.
My only suggestion would be adding some run/bike/run combos into your training. You need to get use to how it feels to go from the bike to run especially.
Well, good luck! You should do just fine.
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather, to skid in broadside thoroughly used-up, totally worn out, and loudly proclaiming: WOW WHAT A RIDE!!!!"