According to USA Triathlon 5.10, there is no drafting (a.) (being in a 7m x 2m zone behind the rider in front of you) except in the case you are passing (h.1.), in which case you have 15s to pass (g.) as measured by your front wheel.
My primary question is, what happens if the rider in front of you happens to decide 5 sec into your passing attempt to pass the rider in front of them -- you've encroached their drafting zone but are going to same speed as them so are unable to pass them within 15 sec? If you drop back you're penalized, but if you continue to attempt to pass you're also, still, penalized?
Also, please address whether during the passing scenario above whether you can immediately enter the draft zone of the rider in front of you without first moving 2m to the left (i.e. can you ride up directly behind the rider, then move to the side to pass)?