IOM ICA have ratified the changes to sail number and identification as per IRSA Supplementary Class Rules 2020. They can be found here: https://1drv.ms/b/s!Atz9OfO56dYKhMdnzEjHl7zp7f4A3A
Guidance notes for implementation of these rules, see here: https://1drv.ms/b/s!Atz9OfO56dYKhOh5Q5oBMGSHW82puw