FWIW, our district has made some changes up through Algebra II as we align with common core (or at least I assume the changes were due to our district's decision to adopt common core - it's a little weird in that there was a lot of publicity about common core when the decision was made a few years ago, but the way the post-adopt-common-core math curriculum changes were explained doesn't refer to common core, just to a "recent change" in curriculum specs lol.
Answering the question "where is it best to compact? For kids who are good at math, I'd do it asap starting in early elementary. All I've seen over and over again in elementary school curriculums is spiral spiral spiral (no matter the curriculum used). My middle school dds are now using a math series of textbooks that are relatively new and I believe intended to follow common core, and I'll be honest - I wouldn't know where to start skipping over things, or compacting, or whatever... because the math books skip all over the replace, then repeat things that they learned years ago. Sometimes I honestly feel like my kids should have just skipped their entire elementary math program, it's that crazy-jumbled-up!
Sorry, I don't have much help to offer
polarbear
