There are a lot of good reasons to go with a self-created calendar table in Power BI instead of using the Auto date/time feature provided by Power BI. This InfoCard shows what I consider the most important ones. It contains everything you need to get started with using calendar tables in your models...
The stability of your BI solution is important. It is particularly important if you provide reports for a large number of users in your organization or as a service for paying customers.
An often overlooked but crucial aspect for stability is your development and deployment process. Customers therefore have a wide variety of procedural and technical requirements for such a process. I have summarized the most common ones...