When i tried to e-file, I got a message stating that the intuit electronic filing center is not yet accepting returns for 2019. When is it opening?

Should be latter in the day.

E-filing now just means your tax return will be sitting on the TurboTax servers until the IRS opens there systems to 2019 tax returns, which may be late in January.  So if you e-file now and then need to make a change to your tax return, you will not be able to.