The main changes in IRSPP v1.3 are (i) to support the IRS test data released by EUMETSAT in July 2024, (ii) to remove obsolete HT-FRTC functionality (which is no longer supported in RTTOV) and substitute equivalent functionality for PC-RTTOV, (iii) to update the output BUFR sequence following user feedback. Further details at https://nwp-saf.eumetsat.int/site/software/irspp/