I sent out my amended tax return and haven't got it back yet its now September

In normal times it takes up to 16 weeks or more to process an Amended 1040X return.  But these are not normal times.

Sorry the IRS has limited staff due to Covid-19.  They just started opening the mail in June that's been stacking up. Back in March the IRS closed their processing centers and stopped processing mailed tax returns.  An IRS spokesperson recently said that they have about 11 million pieces of unopened mail.  The IRS says....."We’re experiencing delays in processing paper tax returns due to limited staffing. If you already filed a paper return, we will process it in the order we received it."  So it may take longer if you mailed in June or later.   So you have to keep waiting.

See this IRS page for the latest information

https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue

Then once they start opening the mail, After 3 weeks you can track it here,    

https://www.irs.gov/filing/individuals/amended-returns-form-1040-x-/wheres-my-amended-return-1

   The IRS has not been working on mailed returns until very recently---and an amended return could  only be filed by mailing it in until last week when e-filing became possible for 2019 amended returns.  Under normal circumstances you would be able to see something about your mailed in Form 1040X after about three weeks, but that is not the case right now.  The usual 4 months for processing an amended return is going to take longer.  Sorry.

https://www.cnn.com/2020/04/20/politics/irs-mail-trailers-covid/index.html

MAILED RETURNS

Per the IRS website IRS Operations During COVID-19: Mission-critical functions continue:  

IRS operational status and alternatives

Processing Delays for Paper Tax Returns: Taxpayers should file electronically through their tax preparer, tax software provider, or IRS Free File. 

We’re experiencing delays in processing paper tax returns due to limited staffing. If you already filed a paper return, we will process it in the order we received it.

Do not file a second tax return or contact the IRS about the status of your return.

 If you mail a tax return (or a payment) to the IRS, it is a good idea to use a mailing service that will track it like UPS or certified mail so you will know it was received.

 TurboTax will not know anything about your amended return, and nor will TT know that you put your 1040X  in an envelope and took it to a mailbox.  TurboTax does not get updates on mailed  (or e-filed) returns.

When the IRS finally opens its mail and begins to process mailed returns you can check the status on the IRS 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...