US TSYS/SUPPLY: Thursday's 20-30Y Buyback Set At $6B

Treasury will buy back up to $6B in 20-30Y nominal coupons in its liquidity support operation Thursday at 1:40 to 2:00pm ET. * This is just the second of the highly-touted upsized long-end buybacks announced in August, following the 10-20Y operation on September 10. * The 10-20Y op was seen as a bit of a disappointment at the time in that Treasury only bought back $5.19B of the maximum $6B. But offers had averaged $19B for that bucket in the preceding 6 operations, vs $36B for 20-30s; it would be a bigger surprise if Treasury didn't buy back the full amount tomorrow. * The next long-end operation after tomorrow's is on Oct 1 (again, at least $4B but final amount yet to be announced).