mention that forward compatibility will be added later

RFC/RFC001.md

@@ -46,6 +46,8 @@ The storage format will be used by git-secret-tell as follows:
 1. Scan the set of `.gpg.colon` to find all currently told identities. If the told identity is in the current list do nothing. 
 1. If the told identity isn't listed run `gpg  --armor --export` against the users `$HOME` keyring. Run `--keyid-format long --with-colons` of the exported key. The result being two new files `<key-id>.pub.gpg` and `<key-id>.gpg.colon` in `~/.gitsecret/keys`
 
+Note that the steps to ensure that older versions of git-secret know about the newly told user will be outlined below. 
+
 The storage format will be used by git-secret-hide as follows: 
 
 1. The list of "64 bit keyid"s who are told will be computed from the `.gpg.colon` files. This will be checked against the list of "64 bit keyid"s in the "keyring cache" at `~/.gitsecret/cache`. Any missing keys are imported into the "keyring cache". It is anticipated that `grep` and `gawk` will be suffient to be perform this calculation. The code then runs as normal using the keyring cache.