It's a tricky one. The /r/coronavirusuk mods are strict AS FUCK and have very itchy delete post fingers indeed. But I think I agree with their stance here assuming it's the same sub. Based on my visits there I don't think they would ban honest, good faith concerns (like say, asking about the safety of AZ). They would ban antivax narratives (whether overt or too obviously trying to hide it as Just Asking Questions) because they know a lot of people use that sub and swallow everything that's posted without question and so it'd be dangerous.
let's be honest, when someone has a firm antivax stance, and isn't just genuinely worried, they tend to have a narrative and a fixed position you won't be able to shift them from in a month of Sundays. But people who are just a bit concerned needn't assume the antivax label applies to them.