Short cut to change highlighted region mode for piano roll?

I've accidentally pressed a shortcut that has changed the default mode where highlighting multiple instrument regions (keys, bass etc) in a cycled area and double clicking on them will open the piano roll to show those selected instrument regions to now when I highlight multiple instrument regions it opens the piano roll but only shows all of the regions of whichever instrument region I click on - so if I highlight them all and then double click on the bass region of the selection, it will then show all of the bass regions in the piano roll.

I've tried various search combos with the words 'select' and 'regions' in the key commands menu but nothing seems to revert it back.

Does anyone know what this key command is so I can reverse this and then nuke the key command form orbit?