In Develop mode my catalog toolbar has two versions depending on the photo I'm working on.
Means some have been processed in Process Version 2010 and some in PV2012.
Lightroom Help | Develop module options
Understanding Lightroom Process Versions - Digital Photography School
Awesome! I had googled all sorts of ways trying to find the solution. Had looked on the Adobe site but my wording must not have been correct.
Retrieving data ...