re: UVXY and SPY are completely disconnected today,
VIX is based on 30-day SPY options, meaning currently calc'd based on SPY options expiring in january, ie: after the end-of-year fund ROI window-dressing rally will cease.
in this case, won't surprise me if we see major SPY selloff in the first week or two of jan.
so VIX and SPY might be less in sync the next couple weeks until VIX is calc'd on late jan SPY options.