One note, I believe he said he was on his stock ticker during his interview with DD in Feb 2017. The watching fish comment was his later interview. I've always wondered if LE told him they had someone who saw him on the platform of the bridge, which is why he then said that about the fish...
This is one of the key pieces of evidence, imo. To overlay it with RA's phone data could be significant, unless the phone data is strong the other way. Jmo.
One thing that certainly happened is when they had probable cause against RA for the search, they also had PC to get his phone records - or at least by the time he was arrested.
IMO they certainly have RAs phone activity for an extended period around the murders, though what actually could be recovered years later might not be everything, and might also depend on what kind of device he had, and what he backed up to cloud etc.
My theory, which of course could be wrong, is that RA's phone data does not corroborate him on the trails either as per the defence case, or as per the prosecution case.
IMO if it corroborated the defence case, it would be in the Franks for sure. He would also never have been arrested IMO.
As usual this is what the defence is not mentioning, when they claim this geofence data is exculpatory.