From November 1st there are Bridge CALs available for Open Value customers.
When do you need a Bridge CAL? Well, if you’ve got an enterprise wide commitment to Office and a CAL Suite but want to transition to either EMS or Office 365 then you need a way to continue to pay for the on-premises components that haven’t transitioned – and that’s the Bridge CAL. They’ve been available in the Enterprise Agreement for a few years and now Open Value customers are able to buy them too.
See page 14 of the November 2015 Product Terms document.