How long before a new Patreon is given access?

[JammyDodger]

According to the guide, the sync job is run 4 times a day as a default:

@Falco

Configuring the optional Patreon Webhook

The Discourse Patreon plugin runs a background job 4 times a day to sync users on your site to groups that you have linked with Patreon. If you would like the syncing to happen faster than that, you can configure a webhook to trigger a new sync every time someone signs up for a reward tier on your Patreon account.

To do that, first visit Patreon and create a new webhook that is pointing to https://discourse.example.com/patreon/webhook