Note that we decreased the local TTL intentionally to something very small to improve on the situation where a former blacklisted domain is now whitelisted. With a high TTL, the client's operating system may just decide to still cache the blocked domain instead of re-querying the (now permitted) domain from the Pi-hole. Just be aware of this limitation when you increase your local TTL manually, but since you aren't using any blocking lists with Pi-hole this shouldn't matter for you.