Enable issue link from issues to tests wrong way round

Before we installed Zephyr we had a Tests link set up as Tests / Is Tested By

When I use this relationship with "Enable issue link from issues to tests" they come out the wrong way round  

e.g. Issue 'tests' Test  rather than Issue 'is tested by' Test.

Does anyone know what can I do to resolve this without disturbing all the correct links that are currently in place?