WildFire Provides near real-time malware and antivirus signatures created as a result of the analysis done by the WildFire public cloud. WildFire signature updates are made available every five minutes. You can set the firewall to check for new updates as frequently as every minute to ensure that the firewall retrieves the latest WildFire signatures within a minute of availability.
Without the WildFire subscription, you must wait at least 24 hours for the signatures to be provided in the Antivirus update.
https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-admin/software-and-content- updates/dynamic-content-updates

The precedence is from the top down; First Match Wins: 1) Block list: Manually entered blocked URLs Objects - 2) Allow list: Manually entered allowed URLs Objects - 3) Custom URL Categories - 4) Cached Cached: URLs learned from External Dynamic Lists (EDLs) - 5) Pre- Defined Categories: PAN-DB or Brightcloud categories.

https://docs.paloaltonetworks.com/pan-os/9-0/pan-os-admin/app-id/manage-new-app-ids-introduced-in-content-releases/review-new-app-id-impact-on-existing- policy-rules