There are many ways to hedge against a rise in interest rates all of which can be found online.he couldn't hedge against rates as suggested. dropping £900bn of debt on the market would raise borrowing rates a great deal, and screws up the rest of the bond market. hence why no other country did anything similar. it was a fringe idea by a lone acedemic.
The Grauniad (via The National Institute of Economic and Social Research) also found Sunak culpable for failing to insure the risk
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Rishi Sunak ‘wasted £11bn by paying too much interest’ on UK debt
Labour accuses chancellor of wastefulness for failing to insure against interest rate rises
As did the FT
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Rishi Sunak blamed for losing £11bn in servicing UK government debt
Treasury failed to take out insurance against rate rises on almost £900bn in QE reserves, say economists
I stand by my comment: "Sunak is an idiot" and has cost this country billions.