Thanks for the response.

That dialogue usually appears when I make a change in the already e-filed return, not when Intuit does an update, as I recall. Although, I think it came up on every return with a Recovery Rebate Credit after Intuit did an update which created quite a disturbance in the force since no change was actually made. Many preparers on this forum thought the IRS had rejected the return and removed the RRC, but it was just an Intuit update glitch. Fortunately, the All-Stars, as they will always be known as to me, spent lots of time and energy calming fears and assuring other preparers that it was Intuit, not the IRS, that created the issue and their e-filed returns were not changed.

I have not checked the box you referred to.

Do not remember being able to lock 2017 files, but time flies in taxland so I'll take your word for it. However, locking the file prevents nothing from automatically being changed, due to an update, if you have to open it again for any reason, so the file is never truly locked or safe. Hence, the reason for my ask.