I am not sure where to report this but I believe I have found a bug in the latest Office 365 product. I set up a machine running windows 7, and implemented Office 2010 and Office 2013 group policies, I scoped the policies to the correct user and machine. the particular policy I am interested in is the "default file format" found in the GPO under the save option for word, excel and powerpoint. under office 2010 this policy applies correctly and does not display the "choose a file format" dialog box when those programs start, this is the behaviour I am looking for. I then installed Office 2013 and implemented the exact same group policy, the default file format dialog box does not appear. however, when I install Office 365 (2013 edition) the dialog box does display. it appears that some other policies do apply correctly to the office 365 product but the default files format policy does not, office 365 is ignoring this policy setting.... hence why I believe this is a bug. according to the Microsoft technical literature the Office 365 product and Office 2013 share the same group policy settings, I can not find any admx files specifically for office 365, only for office 2013 so 365 should recognise and use this policy setting.
Steve