I have tested it from Banshee 1.6.0 on Ubuntu Lucid to Banshee 2.6.1 on Ubuntu Saucy. 
Schema 39 to 45
https://git.gnome.org/browse/banshee/tree/src/Core/Banshee.Services/Banshee.Database/BansheeDbFormatMigrator.cs
"Grouping" was introduced in schema 19 2008-08-19

So what we need from the banshee database seems to be very stable. :-)