With 30 some ships to dispose of, reefing will renter the picture. The only ship recycler on this coast just got shut down, I think there are only 1-2 legt outfits left back East. When the ARSBC went about sinking HMCS Annapolis, Environment Canada changed it's regulatory process twice during the project(grrrr). The RCN also certified she was PCB free, but PCB's were found in the wiring, which the navy had to pay to remove. The reality is that if you are going to prep the vessel to meet the new Hong Kong Convention rules, then the cost of prepping for reefing is about the same. One advantage of reefing is that you can seal up all the asbestos into a certified oil free space and let it go down with the ship. That saves you big bucks as you reduce transport and disposal cost.
The society will no longer take the ship but will advise on meeting the cleanup regs, find the sink location and look after the EC/DFO and TC permitting requirements. Plus design a good sink plan, including controlling flooding and explosive charge placement. Another advantage is that the recycling of components off the ship high grades the more valuable metals and eliminates almost all of the carbon emissions that you get from cutting a ship up. Also FN groups are generally onboard (well not literally) with sinking of them thanks to the proven benefit to rockfish and other reef dwellers.