Renegotiating the contract in a side deal to benefit this captain is crazy. This might be beneficial for this captain because he hasn't found someone to trade with but what happens when upgrades are on the table next time. A senior captain wants to delay their training to a specific date in the future for whatever reason, They can only slide down to where junior pilots have agreed to allow the blanket swaps.
The deal is the deal. Next contract ask for changes. Eat the S@@t sandwich this recession and poor management planning has dealt but don't claim it's for everyone to prosper. It's purely a grab for a piece of what someone else worked out in their swap.