remember how we've seen bts for s4 where noah is at rink-o-mania in a different costume than the one he actually wears there?
and remember how we also got a bts photo of him in a stunt harness in that same costume?
i've seen a lot of people theorize over the last few years that these photos are because they filmed shots during s4 filming that are going to be used for vecna visions in s5.
but there's one thing that's always stuck out to me about this!
every time we see someone in a vision, they're always wearing the clothing they're wearing irl when they get vecna'd, even if they're in a memory.
now, if will get's vecna'd in s5, why would he be in clothing from s4 during the vision?
i definitely think this could be because we see a memory of will's from s4 at rink-o-mania that we haven't previously seen, and we see s5 will witnessing it, but that still doesn't explain the photo with the harness!
if s5 will is witnessing s4 will in a memory, anything requiring a harness (being thrown, lifted, etc.) would be happening to s5 will, not s4 will.
onto my theory:
this might be wishful thinking since i really want to see mike get vecna'd in s5 (i love him and want to see what the hell is going on in his head and think there's soooo much potential there) but i think these photos could actually be explained by a mike vecna vision in s5 rather than a will one.
we know from vol1 that mike is acting a lot kinder towards and protective over will than in s4, so i don't think it's that far of a leap to say that he probably feels guilty about how he acted during their time in california.
remember this scene from s4? where max is talking about her insecurities/shames and vecna puppets lucas to terrorize her?
and remember this one? where vecna-as-brenner breaks the fourth wall of the memory and starts talking directly to nancy?
because of all of this, i think that, potentially, we could get a scene where vecna uses mike's guilt to terrorize him by puppeting will to say horrible things to him, like we see with lumax.
now, remember that outfit we saw from the rink-o-mania bts? where does will wear that outfit?
the van scene.
i think there is potential for us to get a scene where we see mike experience/watch a different/his own pov of the van scene, then vecna-as-will turns to him and breaks the fourth wall of the memory to taunt him. this would then shift location to the roller rink (probably empty except them, like max's snowball memory), leaving vecna-as-will in his van scene outfit with a s5 mike at rink-o-mania.
this is also added to by the fact that the van scene took 12 hours to film. i definitely think that they were shooting additional things during that time, likely for s5!
i'm honestly not sure where the harness thing would come into play. maybe vecna would puppet s4-van-scene-will into doing something that would require a harness during mike's vision, though i can't conceptualize what that could be lol. but i just can't see a use for it if will is the one experiencing the vision!
this is all pretty far-fetched and would require a crazy amount of forethought, planning, and insane composite shots, but the duffers are the duffers and i wouldn't doubt them tbh
(also, i don't think this will actually happen, but on the very slim off-chance it does, i'd like it on the record that i predicted it.)