Hi @wambacher
Thank you for your question!
If you're sending members of your team invitations using "Invite New Member" (email invitation), this "Email Invite Salt" can be manually regenerated in the System Console under "Security" --> "Signup".
If you're inviting members to a team using "get team invite link", this link does not "expire" unless it's regenerated in "Team Settings" by a Team Admin.
Does this help?