During the research stage of earning my platinum for Tomb Raider, I read on more than one occasion that salvage could actually be farmed while in private matches and furthermore, that it could be done solo. A little more research revealed that the same was also supposedly true of XP, now while I didn’t think all these people were collectively lying, I was somewhat sceptical and quite confused. Reason being, I’ve never come across a multiplayer game, where progress made in private matches is saved and actually carries over into public matches.
So I decided to check for myself, I created a private match, started it up and sure enough the game got under way with just me in the lobby. I then proceeded to complete the objectives and crack open a few crates along the way, when the round ended I opted to return to the lobby, noting that the game was saving some data. I then left my private lobby and began searching for a public match, after some time I was plonked me into a public lobby, where I was able to confirm that both salvage and XP earned privately, had indeed been saved and carried over.