Lewis should debut either in June (after the likely Super 2 arbitration cutoff, like Correa and Lindor) or mid-April (after the 7th year of control is guaranteed, like Kris Bryant). These dates are largely irrelevant for the vast majority of players, but Lewis looks elite and thus they carry some significance, especially as a position player. Yes, the service time may prove irrelevant like it has for Buxton and Sano, but you have to cover that base in advance. The only question now is how quickly he can get through AA and AAA and stay healthy. June 2019 is probably a little too fast -- but it would be exciting! April 2020 seems like a good bet now, assuming health, with a fallback of June 2020 or April 2021 if he is slowed by an injury in the meantime. If the Twins deviate from those dates, it would be nice if his call-up was accompanied by a contract extension, buying out his arb years and at least one FA year.