I received an email stating the 540A form is ready for me to complete my tax return but I already filed my taxes and been accepted?

Your "availability notification email" for Form 540 came after the form was available to you within TurboTax.  If your California state tax return was accepted, you do not need to do anything.

My emails have not referenced any particular form. I did not receive any email from the IRS immediately following the transmission of my return specifically a form 540A. As stated, my returns have been accepted by both my state and the IRS.