If the e-file was accepted, you will need to wait for your return to be fully processed and then amend to correct your filing status. And when you file married filing separately, there are some rules to follow. Both spouses must file the same way---either you both use standard deduction or you both itemized. It cannot be one of each. Each of you is required to enter some information on your own return about your spouse. If you are in a community property state, it becomes more complicated.
Wait until your original return has been fully processed before you amend, and make sure you have saved a pdf of the original return before you amend. (If you do not save it as a pdf, the amended return will overwrite the original, and the original will be lost forever)
See this TurboTax support FAQ for amending a tax return -
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Same situation except my husband filed married filing separately first and I haven’t filed yet. If I filed mine married filing together before the deadline, then would the IRS ignore his filing separate and my MFT essentially would replace his return?
You would need to amend his return to change the filing status to Married Filing Jointly and add your information. Another return with his name and SSN will be rejected.