You can not. 

It is often a good idea to do the input in 2017, maybe not all the detail, but at least the big numbers. Get the return to match what was filed, verify depreciation and how the state is computed. That will also give you carryovers.

IF YOU ARE REP, use all 9's for the EIN and there will be no charge. After you proforma to 2018, change the EIN to the real thing.