TurboTax has no way at all to track a tax return that you mailed. The software does not know that you put your return in an envelope and took it to a mailbox. Anything you are seeing as "accepted" can only refer to a return that you e-filed---not one that you mailed. So that is referring to the original return that you e-filed---not an amended return that you mailed.
And you are correct--mailed returns do take a long time to be processed, especially amended returns, which take 4-6 months. Eventually you will be able to track it on the IRS amended return site:
https://www.irs.gov/Filing/Individuals/Amended-Returns-(Form-1040-X)/Wheres-My-Amended-Return-1
https://www.irs.gov/filing/individuals/amended-returns-form-1040-x/amended-return-frequently-asked-q...
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
