You should be filing a Part-Year California return and a Part-Year New York return. The New York returns are tricky - be sure you carefully review the "allocation" - division of income - questions. Don't rush it.
The TurboTax software decides what return to file based on your
entries in My Info. If you
return to the section My Info -
found in the left bar - and then choose Edit by your name, the second section is
titled "Tell us the state(s) you lived in."
The first question is your State
of residence (on December 31, 2017): New York, and then there is a
radio button for I lived in another state
in 2017. You want to be sure it is marked Yes,
so you can enter your Previous state of
residence (where you lived before moving): California.
