I've generally been running most of these slices with 1mm retraction, which I thought was a fairly low retraction level, though I could try cutting back more. Better to lower it, or just turn off retraction just in case?
I thought I'd run a no z-hop attempt, though I may not have. Either way, I have definitely run with z-hop and z hop on retraction, and there are dozens of those Z-hops during the support/brim phase and the adhesion works fine, and it's very consistent that the problem kicks in immediately when the supports are done. Unless there is something different with the z-hop for the change, I would think that the problem would arise at any point if it was caused by z-hop.
(Currently I've been shifting the z offset lower and lower on consecutive attempts, and the supports came out looking printed way too close to the plate on the current print but it just started the actual model and it's got some adhesion(not the cleanest look, but adhering)).
I didn't think the amount of extrusion/height of printing would actually vary between supports/actual model, does it?