what happens to account name and aliases I use, if I leave Runbox?
Do they become available for other users after some time or are they forever reserved and not reused?
I mean aliases in runbox.com domain.
Usernames and aliases are permanently reserved to protect the privacy of the original user.
We only recycle them on request and if the person requesting the username can show they were the original user. As you say this only applies to our own domains as other domains could change hands and whoever owns the domain at the time is entitled to create addresses on them so we allow that. I hope that helps.