Bitcoin's BIP-110-enforcing chain branch stalled at block 961,633 on Sunday after producing only two blocks, while the non-enforcing chain advanced to block 961,721 — widening the gap between the two chains to 88 blocks.

According to the BIP-110 monitor, last updated at 10:19 a.m. UTC, the enforcing branch's most recent block had been mined approximately 12 hours earlier. Ocean records show that a pseudonymous mining group identified as Roughnecks produced the branch's first two blocks using Ocean's Decentralized Alternative Templates for Universal Mining (DATUM) mining protocol.

The chain divergence began after BIP-110 entered its mandatory signaling phase at block 961,632 on Saturday. Only 51 of the preceding 2,016 blocks — approximately 2.53% — had signaled support for the proposal. During the mandatory signaling window, BIP-110-enforcing nodes reject any blocks that do not signal support through version bit 4, while standard Bitcoin nodes continue to accept both signaling and non-signaling blocks. The result is effectively a network partition: transactions confirmed on the enforcing chain remain valid on the standard chain, but the reverse is not guaranteed, since the enforcing branch does not recognize blocks lacking the required signal.

Bitcoin's difficulty adjustment occurs every 2,016 blocks — roughly every two weeks — and the enforcing branch must mine through the remainder of the current adjustment period before its difficulty can recalibrate downward. With only a single mining group contributing hashpower, the branch faces roughly 1,400 remaining blocks at the current difficulty level. Without substantially more hashpower committing to the enforcing chain, progress is expected to remain slow.

Under the BIP-110 proposal, mandatory signaling continues through block 963,647. If the signaling period concludes without a majority of hashpower backing the proposal, the rules would not activate as a consensus standard across the broader network, leaving the enforcing chain as a minority fork. The Bitcoin Improvement Proposal aims to address arbitrary data embedding on the network — a practice amplified by the growth of Ordinals inscriptions and BRC-20 tokens since 2023 — which has fueled ongoing debate within the community over what constitutes legitimate on-chain data.

BIP-110 has faced opposition from prominent Bitcoin figures. Strategy executive chairman Michael Saylor said he shared the proposal's objectives but argued that its approach threatened Bitcoin's neutral rules and consensus mechanism. Blockstream CEO Adam Back warned that the consensus-level change could damage Bitcoin's credibility and potentially render certain unspent transaction outputs (UTXOs) unspendable.

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