The solution we have for that in mind would be a moving average over at least 10 months. That would mean the moment you put down a higher rate it will not increase your payout as fast and while each month gets you closer to your target rate the repair service will move pieces away from your node.
That would be one idea how it can be done. We would announce that in advance and give all the nodes enough time to adjust their configs. For now you can change the rate when ever you want and it will be applied on the next payout calculation.