rhinopham, no, you don’t have to wait for the through to appeal. You can appeal every year as long as prices continue to drop. If, every year, you can show 3 comparable properties at lower prices, you should get a continual downward adjustment until the market hits bottom.
When the market begins to recover, leave it up to County Assessor to adjust the assessment upwards as they have time or remember (they “forgot” to reassess Duncan Hunter’s house until the UT mentioned it. They are still looking into it).