buy incremental, and it could go down further because we do not know when the silver price will correct. next year, there could be major downturn in world-wide and silver can do dive back to $20 or less. But it could be next year march or may. for short-term correction, look for chinese government interest rate hike. when that happens, silver will correct for 10% or so, but after it may go up again.
i think due to ZSL decay, it is prudent to short SLV for long-term holding. I will use both ZSL for short-term and SLV for long-term short. It is for sure that silver prices will correct, but it may not come in a couple of weeks, more likely in a couple of months or more.