Group Policy support for Microsoft Office 365 Business Premium

Hello

We recently switched subscription from 365 Pro Plus to Business Premium.  Prior to installing the new version on every user PC, we tested our existing GPOs with the new version.  Everything worked normally.  Following the change to the actual plan, the GPOs have stopped applying.  We were assured over the telephone by a MS representative that everything would continue working.  Can anyone shed any light on whether GPOs should be applied for Business Premium?

Thanks

Paul