I have been on a waitlist for a Tesla Powerwall for a year and still no estimate of install time. I have just ordered a Skybox and plan on powering it with some Nissan Leaf battery modules I had from another project. If the Skybox gets delivered soon I will cancel the Powerwall order. I will give up the California Self Generation Rebate Incentive Payment on the Powerwall but will then be able to program the Skybox to load shift and arbitrage with more flexibility than I would have under the SGIP. In addition, since I can obtain more Leaf Modules at $200 per kiloWatthour I can incrementally increase my capacity based on my needs as they evolve.