The Almanac extracts available on this website are up to date, and incorporate amendments provided through the NtM service.
Each new edition of the Nautical Almanac (available annually from 1 July) contains a note on page 1 stating the last NtM update applied to the publication before print.
It is the mariner's responsibility to update their copy of the Almanac with any corrections and updates communicated through NtMs.
Page 2 of the attachment below provides a table for recording that amendments have been made to the Almanac.