CFrame and Position being buggy after Weld / Tween?

This one's a weird bug, basically I have a small animation that I play out using a Tween but since there are multiple parts I decided to weld every part to the center one. The animation itself works out fine and once the animation stops I anchor every part and delete all the welds, except theres one issue.

For some reason after the animation is over attempting to edit the CFrame or Position of any of the parts teleports them back to where they were at the start of the animation, I tested with it a bit more by trying to add 1 to the X of one of the parts and it puts the part back at the start of the animation but 1 stud over. It seems like the part still believes its in the starting position despite being moved by the tween and I think it might have to do with the weld.