Just to add my five penn'eth.
The OP's pictures clearly show a 6 wire feed which has been backended from where ever, to provide an NTE and SSFP in that location.
I agree with MHC that back ending is frowned upon.
I also agree with Mr.S, I have never seen back ending cause
any issues.
Leave the bell wire in situ, it has been filtered by the SSFP.