As anticipated, SPY reached my "strong sell zone" and even with drop today, could eventually continue further in the zone. I closed my XIV position two days ago with a +20% gain and yesterday I opened a short SPY position by selling call option (credit or bear) spreads. My previous positions have all been expired and this has been the first favorable opportunity this year to open additional positions.
Using VIX ETFs/ETNs for anticipated shorter term moves (10 - 30 days) and selling credit option spreads when risk/reward is acceptable has work very well thus far.