I had some photos with lots of effects in PSD format (200MB each), I published them on Facebook using Aperture, then decided to convert PSDs to JPEGs to free up some disk space, so I disabled the Facebook account to keep the remote photos while I was exporting and removing local PSDs and import them in JPEG format. Now I wonder if there's a hack to make a link between new local JPEGs and existing Facebook photos? I don't want to publish them again because there are lots of comments and stuff on Facebook, but when I make a change to the picture's title locally or remove some of them I'd like it to be applied on Facebook as well.
I cannot remember where I read it, but there is a tool for converting master files from other formats into JPG and using the JPGs as the new master files. I don’t know if that will retain the links between your Facebook images and the JPG files, but it might be worth a search on Google and asking the tool developer.
Photographer | https://www.walterrowe.com | https://instagram.com/walter.rowe.photo