Due to Labor Day holiday, Monday:
13-wk & 26-wk Auctions will be on Tuesday, 9/5/23.
52-wk Auction will be on Tuesday, 9/5/23 (as typical).
42-day Auction is a CMB, so it isn't on the regular Treasury Auction Schedule. Some brokers may not offer them.
But Settlement dates for these will still be Thursday, 9/7/23.
Orders placed from Thursday afternoon to early Tuesday will be covered by maturing T-Bills on 9/7/23.
Treasury Announcement (note that brokers may have earlier order closing times than Treasury),
https://treasurydirect.gov/instit/annceresult/press/preanre/2023/SPL_20230831_1.pdf
Comments
FWIW, they are also not available through TreasuryDirect. (In reference to another thread, I agree that there is usually little point in buying T-Bills through TreasuryDirect.)
"Cash Management Bills are only available through a bank, broker, or dealer. We [Treasury] do not sell them in TreasuryDirect."
https://www.treasurydirect.gov/marketable-securities/treasury-bills/