Starfinder Society - telling players callback scenarios allowed?
I've run Pathfinder Society and Starfinder Society for 1E and 2E and there are a lot of scenarios that contain references like, "if one of the PCs has played Scenario [insert scenario name here]," they receive a special item, bonus to a roll, or even just a special NPC interaction. I like this, because it helps make the metaplot feel real and like there's connective tissue between all the scenarios in a season. Players are usually pretty excited about it too, as the items and bonuses are often really good. I know that some folks think this discourages new players, but I think Paizo balances it pretty well. The benefits/extra plot points are there, but not so significant that they make it harder to have a good time or participate for a new player or an existing player who's character participated in the previous scenario isn't an allowed level for this newer scenario.
For reference, I mostly GM at my FLGS with public sign ups. I've started keeping track of these callbacks to previous scenarios and telling my players in advance so that they can choose one of their characters that's tied into the background action for the particular scenario being played. Basically, when I list the scenario for sign ups, I just say that there are special benefits or effects in the scenario if they use a character that has played in [insert callback scenarios here]. I do not tell them what specific items/bonuses/NPCs will be present. I only tell them that there are some effects that will trigger if they bring a character that's played in those previous sessions. At that point, it's up to them to use a character who's played in the previous scenarios--or not.
Is this allowed? Is this allowed but I should be spoilering it on event listings? Is this something that Paizo should be doing when they list scenarios so players can make sure their characters get the most involved story arc?