FediTips has moved!I am not a sysadmin but as far as I know relays simply feed into the server's list of noticed posts, alongside posts it has noticed by other methods (user subscriptions, user shares, shares by people the user follows etc).
Hashtag subscriptions don't boost anything, they're just passive filters for posts your server notices anyway.
The hashtag based relay which you've subscribed to is something else, it's an account that actively pushes posts to your server by boosting them.
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