What I could decipher from final rule and draft advisory circular 91-57C. Is that the application process will ask the CBO/requester for boundary lat/long that defines the requested designated area, GIS files are preferable(from draft circular).
from final rule:
“5) the physical address of the proposed FAA-recognized identification area; (6) the location of the FAA-recognized identification area in a form and manner prescribed by the Administrator”
Draft circular states request will require lat/long of boundary of proposed area
But understand your question will only be answered once the FAA releases the advisory circular. That is what we are waiting for.
Sources
Final rule: page 187ff paragraph D
Draft advisory circular 91-57c. Paragraph 3.5.4. Page 3-10 (or page 18 of entire document)
https://amablog.modelaircraft.org/amagov/wp-content/uploads/sites/2/2021/08/AC_91-57C_Coord_Copy.pdf
Understand my post and knowledge/interest does not equal support/agreement with the new rules. Just stating what is known to best of my ability.
And I might have spent some time in aviation safety/failure investigations in a previous life😏