The TurboTax program will display that language for the user, simply as a message that can literally be taken at face value. In other words, the tax returns are indeed complete, and in fact ready for the user to print and mail them to the IRS and applicable state department of revenue.
I do agree that the program messaging here can be a bit cryptic or difficult to interpret sometimes. However, that doesn't mean that there's anything wrong. Unlike when a taxpayer e-files a return, where there is a verifiable electronic "trail" for the TurboTax program to follow -- and then to check with the IRS (and state) computers for confirmation -- there's no such equivalent in the analog paper world.
Expressed another way, the program has no way of knowing that you've already been to the post office, or that the Certified Mail receipts show your tax returns as being delivered. Granted, the program could conceivably do that if it connected with the Postal Service computer tracking system, but unfortunately it doesn't. But, again, this is normal messaging for TurboTax.
In fact, although I am a modern CPA who e-files plenty of tax returns, I still do have occasion to paper file (by mail) some tax returns as well. I can assure you that if you've physically printed (and mailed) your tax returns from the TurboTax program, and you also have your confirmation receipts (Certified Mail) from the USPS, then your tax returns are safely in the possession of the revenue authorities.
While the TurboTax message may appear somewhat troubling, you can safely ignore it. At this point, post-filing, there is really nothing more that you need to do, other than wait patiently for the government to process your tax returns. As I'm sure you do know, paper tax returns take somewhat longer than e-file returns to process . . . but they do eventually get done.
Thank you for asking this question, and for your observation.
