Wrong email signature sent out

When one ticket has 2+ support admins working on it, the email signature that is sent out is of the person assigned to the ticket only, not the person who replies.

Example:
Bob has a signature of “Thanks, Bob”
Jane has a signature of “Thanks, Jane”

The ticket is assigned to Jane.

Bob replies to the same ticket.

The email signature of Bob says “Thanks, Jane”.

In the settings -> Emails -> Reply Added it is set to {agent_signature}