The benchmark will have its last fixing at around 6:55 a.m. New York time on Friday, and some borrowers and lenders are still scrambling to amend contracts.

The Treasury Department will sell an unusually short-dated bill tomorrow, as it seeks to maneuver around the strictures of the debt ceiling.

Large Wall Street dealers already stand to lose $5 million to $10 million if the spread between overnight and term SOFR moves against them by just 1 basis point, and their exposure grows with every new transaction.

$4.6 trillion is currently sitting in U.S. money-market mutual funds, with another $150 billion in ultra-short bond funds.

Quantitative tightening may draw reticent short-term investors back into Treasuries, although some analysts believe that, "from a cash-market perspective, nothing will change when the first bill runoff takes place on Thursday."

The short-term IOUs look increasingly attractive compared with locking in longer-term borrowing in a market beset by turbulence.

If signed into law, the measure will head off uncertainty and legal fights around some $16 trillion of LIBOR-linked deals that may survive beyond June 2023.

Is the market headed to a world with multiple reference rates?