New, as in the yield sign was added during the safe center project. The banner and Mystic Street stop sign are from the old Minuteman alignment, the stop railroad signal is from B&M days.
Note that as planned, there were two yield signs and two sharks teeth. However, the inbound yield sign was never installed but the inbound sharks teeth were. The outbound sharks teeth were not installed but the outbound yield sign was.
Like I said, a puzzle.
-mr. bill