Crypto rules finalized, Bitcoin retreats, Solana upgrades | Weekly recap

In this week’s edition of the weekly recap, US regulators finalized stablecoin rules under the GENIUS Act, Bitcoin lost ground after a sharp reversal in ETF flows, and Solana activated Alpenglow. Corporate Bitcoin financing, institutional custody deals, and Ethereum’s postponed testnet upgrade also shaped crypto.news coverage for Oct. 18–24. Summary Jan. 18, 2027, is the effective date for the OCC’s final GENIUS Act stablecoin rules. $635.49 million left US spot Bitcoin ETFs on Oct. 22, ending three consecutive inflow sessions. Solana activated Alpenglow on Oct. 21, targeting roughly 150-millisecond finality with its new consensus system. Strategy increased its Bitcoin holdings to 848,517 BTC and expanded its securities buyback authorization. Strive closed a $630 million preferred stock offering carrying a fixed 15% annual dividend rate. GENIUS Act rules set January start date The Office of the Comptroller of the Currency finalized stablecoin regulations on Oct. 21, establishing standards for reserve assets, redemptions, risk management, custody and issuer supervision. The rules take effect Jan. 18, 2027, and cover issuers and related activities under the agency’s jurisdiction. Existing issuers with substantially complete applications pending by the deadline may seek temporary compliance waivers while their submissions undergo review. Anti-money laundering and sanctions provisions remain subject to a separate rulemaking with the Treasury Department. The framework also addresses foreign issuers and transitions from state to federal oversight. Bitcoin ETF withdrawals interrupt the recovery US spot Bitcoin ETFs recorded $635.49 million in net outflows on Oct. 22, reversing three consecutive sessions that brought in approximately $1.08 billion. SoSoValue’s figures showed the largest daily withdrawal since June 25, with October’s cumulative flows turning negative by about $174.5 million. Bitcoin traded near $81,450 in crypto.news’ Oct. 23 market report after failing to sustain its recovery toward $85,000. The retreat returned attention to the $80,000 area. CoinGlass separately recorded roughly $406 million in liquidations across the broader cryptocurrency market over 24 hours, rather than Bitcoin alone. You might also like: Bitcoin slips below $80k, Ledger tightens sales, MSCI changes rules | Weekly recap Solana activates Alpenglow consensus Solana Foundation’s activation record confirmed Alpenglow’s deployment on mainnet during epoch 1064 on Oct. 21. The Votor consensus system targets roughly 150-millisecond finality, compared with 12.8 seconds under TowerBFT. Transaction execution, program behavior, and fee mechanics remain unchanged. Alpenglow consensus began at slot 459,653,000 after a genesis block received certification from 446 of 654 validators. Rotor, the proposed data-distribution component, remains reserved for a later release. Solana also promoted Quantumglow research, but the proposed post-quantum adaptation has no announced deployment date and is separate from the completed consensus migration. Strategy adds Bitcoin and expands buybacks Strategy acquired another 267 Bitcoin, bringing its holdings to 848,517 BTC as of Oct. 18. Michael Saylor’s Oct.