The software update came one day (the 26th) after the form was flagged as available. The update took care of it, and e-filing also worked for me today. TurboTax should not put a date of availability which is earlier than the software update. This is quite frustrating. The postings of Experts that don't know the correct answers are also frustrating (see below).
This will be useful for everyone for next year's filing:
The turbotax forms page Federal Individual Forms Availability (intuit.com) has wrong entry:
"Form 4852, Substitute Form W-2 or 1099R available unsupported"
E-filing is supported after the specified date (with the software update) !
The earlier software messages about unavailability of the form as well as the experts' posting on this page are wrong and misleading:
The final form was ready in Sept 2000 (you can check your return now and see the Rev Sept 2020). The issue is only if you could E-file. You could have filled the IRS Form and file a paper version before the 25th - you would have to replace the Turbo Tax page (which had a watermark "DO NOT FILE ..." ) by your page, or, alternatively, if you have a PDF Editor, you could easily remove the watermarks from the the TurboTax generated PDF. The IRS does not accept the e-filing earlier since they want people to do their best to get the W2 or 1099R forms, but they accept the paper filing earlier (I filed it in January before). Of course, you should specify a good reason why you use the substitute.
