It's poorly worded with what they said. Prior to PCCE 12.0, all components had to be the same version. With 12.0, you can have different versions, so as long as it matches the matrix. So you have have Finesse 12.5 with PCCE 12.0 and still be within reference design, meaning, you'll pass the validator. Colleague of mine did it in his lab and it took about 2 hours... it's a full OS upgrade.