Finally talk of replacing tunnel is moving forward. Here is link to long video of the proposed replacement. Evidently the work is going to be done with jjust 2 bores at first but with provision to construct the other 2 bores later. What was not noted in this video is that the freight traffic will remain using th old B&P. That is probably a good idea eliminating possibility of any freight derailment plugging the passenger tracks. Maintaining the old bore will remain expensive.
Record of Decision with technical details for the ‘Frederick Douglass’ replacement: