Textpattern CMS support forum
To Daniel, who wanted wiki access for plugin prefixes
The wiki is deprecated. No new accounts will be given.
(Robert, Phil… you need to take my name/email off the admin email contact for the wiki, please. Edit the About page, etc. And do this, already.)
As for wanting two prefixes, somebody else will have to answer that (and update the prefix guidelines accordingly with the answer), but as for reserving a prefix, write an issue and someone will add it to the prefix listing.