And mostly, I'm glad you made it thru OK. My hat's off to you for being so pro-active during the night, even going so far as to re- anchor. I think most folks would sit tight and hope for the best, especially when singlehanded. That takes some seamanship to do what you did.
I've never really thought of lowering a second anchor to reduce veering, I'll have to keep that in mind. Just curious, did you consider rowing out a second anchor, say to the NW, where you expected the wind to shift to? With not too much angle between the anchors they could share the load, and perhaps lessen the veering. I've used two anchors for a forecast hurricane in a narrow channel where the room was limited, with good results, though in fairness the hurricane ended up more of a glancing blow than a direct hit. In contrast, when anchored in a big protected bay like Southern Harbor a few years ago I only used the single Rocna, which does give a lot more flexibility. Once you have two anchors down you're pretty committed to that spot. Experiences like yours are always great for learning, since we thankfully don't get to experience too many of them
Congrats for getting thru and thanks again for the interesting report.
Max