IF EXISTS doesn't stop errors on RDS Postgres 11.19 instance

Recently one of our RDS Postgres databases was upgraded to version 11.19. Since then, we're receiving errors when running a database migration. I can't replicate this issue locally, it appears to be restricted to the RDS instance only. Running this query on an empty database:

ALTER TABLE IF EXISTS ONLY public.telescope_entries_tags 
   DROP CONSTRAINT IF EXISTS telescope_entries_tags_entry_uuid_foreign;

results in the following error on RDS:

Query 1 ERROR: ERROR:  relation "public.telescope_entries_tags" does not exist

However, when running this on a local database (also Postgres 11.19) I get the following response:

NOTICE:  relation "telescope_entries_tags" does not exist, skipping

Query 1 OK: ALTER TABLE

Note, this code was auto generated inside a pg_restore command, wrapped inside a laravel function, wrapped inside some CI/CD functionality. This is the simplest case I can boil it down to. The code was generated using pg_restore (PostgreSQL) 13.11. I've checked through the differences in all the settings that are shown when running "SHOW ALL;", and copied whatever I could to the local instance, and still can't get this code to show an error locally. I just don't understand why this is classified as an error on RDS. To my mind it should be a notice. Any advice would be appreciated.