The composition of the reserves must be published monthly on the issuer's website
What the document says“publish the monthly composition of the issuer's reserves on the website of the issuer, containing-- (i) the total number of outstanding payment stablecoins issued by the issuer; and (ii) the amount and composition of the reserves described in subparagraph (A), including the average tenor and geographic location of custody of each category of reserve instruments.”
Subsection (a)(1)(C). Two things go in the monthly posting: the total number of outstanding stablecoins, and the amount and composition of the reserves, including the average tenor of each category of reserve instrument and where each is held in custody.
What the document actually says“publish the monthly composition of the issuer's reserves on the website of the issuer, containing-- (i) the total number of outstanding payment stablecoins issued by the issuer; and (ii) the amount and composition of the reserves described in subparagraph (A), including the average tenor and geographic location of custody of each category of reserve instruments.”
Each month the maker must post what it holds. It must give the number of coins out there. It must say what the backing is and where it is kept.
Tenor means how long until an asset comes due. The posting goes on the maker's own website. Anyone can read it.
No action is recorded against this proposal. That is not evidence that none has been taken, and nobody has yet read it against the record. See what the tracker does not yet cover.