Thank you for your response.
Note, though, that the instructions for form 8283 (revised Dec 2024) explicitly state: “Also file form 8283 for any carryover year described in section 170 (d)”. Presumably this refers to submitting a COPY of the original 8283 that was filed for the year of the donation. But that, of course, cannot be efiled. For earlier years, IRS allowed efiling of the return, with a subsequent submission of a paper copy of the signed form 8283, using form 8453, but IRS seems to have disallowed that possibility for 2024 — at least for donations over $5,000. That seems to imply that, even in carryover years, the whole return would need to be mailed in paper form.
