What time of day does the irs start accepting returns and will turbo tax update me once they accept it

The IRS did not announce the time they will begin processing today January 27.  But they will have a big backlog, and you may or may not hear anything today.  Because there are so many, the IRS retrieves returns from TurboTax servers in manageable batches and in no particular order as far as I know.  It's unknown how smoothly it will start off, and there could be delays due to the volume.

When your return is accepted or rejected, you should get an email notification.   You can also check the status by logging into your Online TurboTax account and looking at the efile status on the Tax Home page.