Gosh Karen, you had to tempt me with the refractometer again! 
I feel like I'm boiling blind with my sap. Haha. I must say that I noticed that some of the rims on the buckets where the sap had dried off felt a little sticky. Maybe it's a higher sugar content? Or maybe just my imagination?
But didnt take long for the colour to change in the pans though - compared with the first boil of the season.
Well Im heading off to la la land. Want to get a headstart tomorrow before its supposed to drizzle. Not going to fight the rain boiling without a roof over my head.
Homeschooling mama to 8
2010-30 taps, steam pans on a fisher grandma bear woodstove outdoors. Bottled 18.5L
2012- 70 taps - 20L
2013 - 70 taps, 3 steam pans on concrete block arch. 50L
2015- 70 taps, 50.5L, 3.3lbs accidental sugar
2021 - 120 taps, new-to-me 2x5 flat pan with a cast iron arch atop a brick firebox.