How You Can Change To Another Connection Type In PowerPivot

I have noticed that it has been noted in a couple of places that once you choose to connect to data in a particular type of data source (i.e. an Access ACCDB file or a SQL Server or MySQL database) you are then subsequently unable to change the type of data source for PowerPivot data (say if you migrate your data from Access to SQL Server after building a big PowerPivot solution). This could have major implications on a complex PowerPivot solution with lots of DAX functionality and Pivot Tables based on the existing tables. This would be a painful process no doubt