Hi Wayne, first of all, welcome to the LOC.
Let's see if I'm reading this right. Hopefully, you purchased your car last week, a 2014 CT200 from a Lexus Main Dealer? Is it a pre approved pre owned? if so, it comes with a 1 year full equivalent manufacturers warranty. I can't work out why a 2014 car's warranty will run out in March 2018, but that's by the by.
The Hybrid Batteries are covered for 5 years from manufacture.The hybrid health check isn't new, I think I've had mine included in the service for the last 3 or 4 years.
I don't think you need to worry for the next 12 months, the chances are, nothing will go wrong, but, and I think it's a big but, if it does, the Main Dealer will cover it.
Enjoy your new car (next August you can start a thread on here regarding the purchasing of Warranties)
Graham.