Anyone in need of respite from the roller coaster that is the US bond market was left nauseated Wednesday.

At this point, the long-end of the Treasury curve is a confused rhino. And we’re fresh out of etorphine darts.

Open interest data for Tuesday suggested short covering and steepener unwinds, but by Wednesday afternoon, yields were cheaper by up to 13bps in a long-end-led selloff that also found 10-year yields up double-digits, sharply bear-steepening the 2s10s.

It was déjà vu all over again, with sentiment undermined by a tailing five-year sale that looked even weaker in the context of a decent concession headed in.

Recall that a trio of tails from this month’s three-, 10- and 30-year series rekindled supply jitters, triggering a fresh wave of bearish sentiment just as dovish Fed rhetoric and a safe-haven bid looked poised to catalyze a rally.

The figure above gives you a sense of how wild October was. Or is. It’s not over yet.

The market doesn’t like auction tails at a time when traders are acutely concerned about sponsorship for escalating supply to fund deficits which are no longer being underwritten by the Fed and other price-agnostic investor cohorts. And, as noted here a few days ago, equities are exhibiting rates fatigue.

Real-time commentary on equities during big-tech earnings week is an exercise in futility — whatever you write risks being stale as soon as you publish it. But suffice to say US shares were materially weaker on Wednesday afternoon, and the proximate cause was another escalatory bond selloff.

There’s considerable angst around next week’s refunding. Some have speculated that Treasury, sensing the tension, may surprise markets by tilting issuance more heavily towards bills in an effort to mitigate the supply overhang that continues to weigh on psychology at the besieged long-end.

There’s still $1.1 trillion parked in the Fed’s RRP garage and money market funds are sitting on record AUM. Ostensibly, that means the market can handle more bills, and might even digest them with relative alacrity.

Absent that, or a sudden deterioration in the incoming economic data, everything from five-years on out the curve could come under heavy fire at any time. Just ask Wednesday.

“If [a] Treasury ‘refunding twist’ does not occur, it would be extremely difficult to envision rates rallying into year-end with all the structural headwinds remaining in the background, on top of nominal GDP with a seven-handle again,” Nomura’s Charlie McElligott said, adding that unanchored rates could “challenge equities’ ability” to stage a Santa Rally.