SR67 - A couple of thoughts after reading through your posts.
1.) Don't look for nodes based on the chronograph. Sometimes it works, but other times it'll have you chasing your tail. I would strongly advise bumping it back to 40gr, and working up in .2gr increments. Then, look for vertical on the target. Sometimes it's helpful to shoot at 200 or 300 yards, which will afford you greater resolution on target. Most importantly though, let the target dictate your load development. The chronograph is really just there to tell you if you're in the target velocity range, and for drops. etc.
2.) Once you've identified 2-3 charges that impact a vertical plane, go back and work depth in .003-.005" increments starting from .005 off. You will find a depth node doing this. Guaranteed. Yes it's slow/methodical, but you'll find it every time...and it sounds like you've already burned through a few components trying to fast-track load dev. Burn through a few more and do it right.
3.) I'd limit all testing to one sizing die for now. Neck tension matters greatly, but you're really playing around with too many variables at once (even for an experienced re-loader). I would recommend going with the Type-S and putting .001-.002 tension on the bullet. And do this by measurement (on a sized/non-expanded case), not by what's marked on the bushing, because often times they size differently than they're marked. Mandrel expand if possible, but not required.
4.) Some Creedmoor barrels don't like H4350. Hard to believe I know, but I've had a couple. I will say if H4350 doesn't work all that well, RL16 or H4831SC usually does. RL16 will be a hair faster than H4350, and H4831SC will usually be a bit slower. Still.... .6 MOA isn't terrible, but it can/should do better. I will typically try both H4350 & RL16 on my first outings with a 6.5CM barrel, and I've never had one of those powders not shoot.
5.) I agree with others on the bullets too. 142SMKs and 140 Hybrids are stupid easy to find loads for, but generally so are the 140/147s...they just don't hold together.

I run alpha brass in mine, which I believe has a lower capacity than Lapua, but I can pretty well guarantee every new tube will tune in at 40.3gr-41gr of H4350 or RL16. It's really just one range trip to find the powder node, then just a matter of depth, and it's one holding. 27"-30" barrels will typically tune in around ~2750-2825 for me with most 140 class bullets.
Edit: I'm speaking specifically of the SAAMI .199fb chamber.
Good luck.