When testing in a Local Server (Not Play Solo) in Studio, my MembershipType is set to BuildersClub even though Builder’s Club has been replaced by Roblox Premium.
This shows in the Playerlist as well.
To reproduce, simply start a Local Server in any place in Studio. If you need one, here is the empty baseplate I used: MembershipType Bug.rbxl (17.9 KB)
I’m unsure of when this first starting happening, I first noticed it in Studio around 30 minutes ago and was able to reproduce it in two different places. I do have a Premium membership.
This sometimes happens to me, but it was OBC, not regular BC. However, before Roblox changed it from Builders Club to Premium, I had an active subscription of OBC.
Therefore, like @LucasTutoriaisSaimo asked, it probably hasn’t yet changed from one of the three BC logos to Roblox Premium on Roblox Studio.
It seems there may be a glitch with Builders Club, as @TwyPlasma shows it happening only 7 days ago as of this post.
Also if you notice, Builders Club ads are appearing.
Seems old Builders Club things are popping up, so it must be a glitch unless Roblox was bringing back BC (which the chances of that are so low).