No. The Online version automatically saves each entry you make. So do not touch your real return. You would have to set up a new account to test in. You don't have to You have to actually pay after you upgrade. Go up to My Account and click on Print Center and try to print your 2016 return and it should make you pay unless you want to print it out.
Online is only good for 1 return. But you can use the same email address for 5 accounts. How to start another return in the Online version
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