I think you could be misunderstanding how it works.

Option #1 (the default rule), part 1:  Continue reporting the old asset, using the original place in service date (so it depreciates for 18.5 more years)

Option #1 (the default rule), part 2:  Any excess/additional Basis, start depreciating using the new "placed in service" date.

Option #2:  Depreciate the entire Basis (both Adjusted old and new) using the current "placed in service" date.  Manually keep track of prior depreciation for whenever it sells.  Be sure to check to box on the Asset Entry Worksheet to elect out of §1.168(i) rules.