I always think of the Alirio Diaz versions as authoritative, but I could be wrong.
In that version the time signature is listed as 3/4 6/8, and I am not sure what that implies. Maybe that it alternates. You can see it here:
https://www.slideshare.net/Pachanito...-antonio-lauro
Also some very useful information here by Luis Zea, where he talks about the waltzes, and this particular piece, and a bit about the 3/4 and 6/8 time:
https://www.siempreflamenco.com/Part...ro%20Notes.pdf