Assuming you are referring to Rev. Proc. 2019-38, which provides a safe harbor to "treat all similar properties held for the production of rents... as a single enterprise", that is not an aggregation that is made in accordance with §1.199A-4 and is, therefore, not subject to the disclosure requirements under subsection (c) of the regulation.

Since such aggregation is not reportable on F.8995-A Sch B (pursuant to §1.199A-4(c)) and the safe harbor election is already subject to a separate set of disclosure requirement, box (c) does not need to be checked.