That hilly 38 miler sounds like a pretty tough one. I'm going to ride the Giro d'Otisco course with another guy on either the 11th or the 18th, we haven't decided which weekend yet (won't be at a hard effort throughout - I can't imagine doing Church Hill Rd. at the end of a race; it's tough enough as a stand-alone). If I have the 18th free, I might try that 38 mile ride. I thought I'd done all the Terrible B hills (spread out over several rides) except for the ones with gravel, like Bruce Hill (the one time I went out there, I decided not to even try it on a road bike). But oddly enough, I hardly ever go South from Ithaca (hate the traffic on 13/34/96 just outside of town), so I've never seen a lot of those hills that far South between 34/96 and 13. If I go South, it's almost always on 96B from the Commons and past IC or via 79/Burns/King to get to Sandbank or Blakeslee Hill. I've always wondered what was out in that area West of 96, though.

So if I'm free, I might join that ride. If I don't hold up the group, that is - my normal average speed on routes that have more than 3 of those Terrible B type of hills is only about 13 mph - or if I'm not too much of a squirrel (I ride solo about 98% of the time and definitely need more practice with group rides).

I've done even the gravel ones including Bruce, and Beech Hill which is even worse -- never again though. This course is an alternative to those gravel (and worse!) B Hills, totally paved.

The hills south of Ithaca are beautiful, nice climbs, great views, nice downhills too. I wouldn't worry about speed, the goal is to finish the course!

BTW have you checked out the Highlander? Their Quads Hilla Century is 105 miles, only 9,000 ft climbing this year (last yr it was 11,000), with some real nice hills: https://www.highlandercycletour.com/rides.htm And fwiw I'm also a 95% solo rider.