Is it possible for master, tempdb, model and msdb to have a database_id other than 1,2,3,4 respectively?

SQL Server [System Databases](https://learn.microsoft.com/en-us/sql/relational-databases/databases/system-databases?view=sql-server-ver15) , as far as I know, always have those same IDs and I have seen lots of maintenance scripts on the internet relying on the predicate WHERE database_id > 4 to exclude them from the actions of the script. Also, if I run SELECT name, schema_id FROM sys.schemas; on a new user database, I get: name schema_id dbo 1 guest 2 INFORMATION_SCHEMA 3 sys 4 db_owner 16384 db_accessadmin 16385 db_securityadmin 16386 db_ddladmin 16387 db_backupoperator 16389 db_datareader 16390 db_datawriter 16391 db_denydatareader 16392 db_denydatawriter 16393 I ran that query on two different instances, one a SQL Server 2016 and the other a SQL Server 2005, and both returned that same result. Questions: ---------- 1. Is there any situation (or sql server version) in which the system databases master, tempdb, model and msdb would have a database_id other than 1,2,3,4 respectively? 2. Can I **really** trust on the fact that the schemas I listed will always have the same IDs on any instance of SQL Server so that I can write maintenance scripts based on those IDs?