As I am sure you are aware, for the last 5 months work has been on-going to create a relative lock-time proposal using sequence numbers. The implementation can be found at https://github.com/bitcoin/bitcoin/pull/6312. The current implementation is "mempool-only" and the soft-fork would be deployed at a later stage.

Over these months there has been various discussion back and forth to refine the details.

I have updated the BIP text now according to the details that were discussed in mid-October[1][2] and have extensively clarified the text.

To recap, the overall picture for relative lock-time is that BIP68 introduces consensus rules using some of the nSequence field, while BIP112 creates a new opcode OP_CHECKSEQUENCEVERIFY (PR #6564) so relative lock-time can be verified from the Bitcoin scripting language. Ideally we would soft-fork BIP68, BIP112 (CSV) and 113 (MTP) together. BIP113 has been deployed in 0.11.2 as mempool policy so miners should be applying this policy as they deploy version 4 blocks for the ongoing CLTV soft-fork (currently at 42% at the time of writing).

I am writing this mail to draw your attention to the BIP68 pull-requests and to request final review at:

BIP68 implementation - https://github.com/bitcoin/bitcoin/pull/6312

Discussion references: