My TY2024 return got rejected because the TY2023 AGI did not match.
I signed into IRS.gov and went through the id.me process, and ordered my transcript.
Sure enough, the TY2023 AGI matched the Turbotax-supplied AGI. So I have several matches.
I talked to an IRS agent on April 16, and she said she couldn't see the numbers despite me being able to read it off the transcript. She said it was OK to try 0. I'll let you know how that goes.