If it really was approved to be a fiscal year end, sounds like the 2019 form is what you are looking for. But you can use a 2018 form and cross off the dates and write in the correct dates if you want to get the return done now.
and ex marks the spot where those rocks and anvils hit me.
Software isn't ready to go, so your options are to do an extension, or do the return on 2018 forms & paper file AFTER changing all the dates on the forms etc.
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