Key Takeaways:
Jon Atack advised users to avoid BTC transactions during the second week of August, citing reorg risk from BIP-110's activation around block 961,632.
Atack posted the warning on X on June 29, saying he plans to run both a custom version of Bitcoin Core and Bitcoin Knots 110 side by side to monitor how the network behaves before the rules take effect.
BIP-110 is a temporary soft fork that limits arbitrary data in transactions, capping OP_RETURN outputs at 83 bytes and witness elements at 256 bytes. Miner support for the proposal stood at just 0.79% as of July 1, according to node data. The mandatory window begins around block 961,632, projected for Aug. 7.
Because enforcement runs through nodes rather than miners alone, a lag in hash power could produce short reorgs, slower blocks on the enforcing side, or mempool divergence once the mandatory window starts. Luke Dashjr countered that upgraded nodes face no reorg risk once BIP-110 locks in, but Atack characterized his position as neutral, presenting the dual-node approach as a means of observation.
Atack's setup mirrors a method available to any technical user. Running a standard Bitcoin Core node alongside a Knots node with separate data directories lets an operator watch both chain tips at once. When a miner produces a block that skips BIP-110 signaling, the Core node accepts it while the Knots node rejects it, creating two live views of the chain on one machine.
For holders who want to reduce exposure during the window, Atack suggested moving funds off exchanges into self-custody before the mandatory period begins, deferring large or time-sensitive transfers until confirmations stabilize, and waiting for six to 10 confirmations instead of the usual one to three if a transaction cannot wait.
If BIP-110 locks in, full data-limiting rules follow roughly 2,016 blocks after the mandatory window ends, pushing full activation into mid-to-late August or early September. The rule then runs for about a year before expiring on its own.
The warning comes as the Bitcoin community remains divided over the proposal. Some users called for active opposition, with one X user urging the community to place large OP_RETURN outputs and inscriptions in every block during the 144-block window. Others questioned why users should sideline funds at all.
This article is for informational purposes only and does not constitute investment advice.
