unable scheduled refresh

To answer my own questions but feel free comment if I mistated anything.  

1.  Oct 2020 Remote Sever Desktop (RS) version has a bug that prevents the refresh feature from working on the report server. Had to uninstall Oct 2020 RS Desktop and installed the May 2020 RS Desktop version.  That fixed the refresh issue.  

2. There are two flavors of PBI Desktop. There is the regular version (PBI Desktop) but also there is the Power BI Desktop Optimized for Power BI Report Server (RS Desktop).  In theory, it should be easy to convert the existing reports created with the regular version over to the May 2020 RS version.  However, all the reports were created in the most recent download of the regular version.  That upgrade included an irreversible feature “enhanced dataset metadata”, that Microsoft did not make clear this feature was incompatible with the Report Server. Consequently, any report created recently in this regular version cannot be opened in go forward May RS Desktop version.  To fix this, I retrieved archived reports that luckily, I created in an older version of PBI Desktop and re-saved them in the May RS Desktop version. This worked as a starting place for some of the reports but any new reports created need to be built from scatch in RS Desktop.

3. The next issue is that the RS version does not allow a composite model.  This limited functionality means that all the tables must be exclusively the same type either import query mode or directly query mode. We have some reports that exceed the capacity of the import mode, so the desire is to use direct qurery for these select cases. Changing the tables to direct query mode has a wrinkle is that all the calendar tables, for all the reports, are created in PBI Desktop which means the calendar tables are in import mode.  This is the standard way of creating calendar tables.   To make the calendar tables operational in direct querry will need to develop a calendar table in the data warehouse.  

Note to point 1 & 2. At this time is PBI RS and PBI Desktop (RS) re-released, and issues mentioned in first two points are resolved.

Note to point 3, in on-premise deployment, is much better use PBI RS in combination with dedicated SSAS tabular instance (for large models), which move limits far beyond standalone PBI RS and also beyond Power BI Pro & Premium limits