JST, the issue has been looked into and fixed. Yours is a very specific bug that has to do with an assembly where the assembly file was relocated to a new machine or folder and where there are multiple subassemblies with identical constituents. There is probably more to it than that, I didn't dig too deeply into dev, but at a high level the takeaway is this bug is unrelated to zoom etc. and can manifest with sporadic behavior related to save, and it has been addressed.
OK, that's good, thank you. I'll keep an eye out for the zoom behavior but for the moment will assume it was a sporadic manifestation of this issue. For what it's worth, it was indeed relocated, but via a package file.
