Basically, if it's not in a trailer or mentioned in a news article, it's a spoiler and you have to do a spoiler tag. There are a couple of exceptions, like we had to do with Eternals, but this is the general golden rule, even if it's something everybody knows about and expects.
And honestly, I feel 99% sure that what you're talking about (trust me I know) will be in tomorrow's trailer, so then it will be free reign. But for now, just spoiler tag.