The title is misleading. The 17 month period is an extension you qualify for ONLY if you have already filed for an H-1B. This means you must already have gotten enough funding to prove that your cash inflow can sustain your salary.
You can stay after the one year period even now provided you file for an H-1B and get it.
This 17 month period is primarily to do away with the period between your OPT expiration and start of your H-1B.