From https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/e-file-amended-state-return/L2JxjObhb_US_en_US it seems like I should be able to e-file amended return for CA state.
But TurboTax Premier won't let me do it now (April 2025) for 2023 tax year.
There seems to be a deadline in Oct-Nov 2023 after which e-file for 2023 is closed.
Is that correct?
Correct. In order to e-file a CA amended return, it must be in the same filing season before the government shuts down and changes software. After that, you must print, sign and date, and mail with tracking - no signature required.
Thanks for your prompt response.
It would be useful to indicate this on the original "TurboTax Help" page that I linked at the beginning of my question. (to avoid the impression that CA, and a few other states, support e-filing amended returns.... without any caveats)