That’s kinda what I thought but I couldn’t find much info. They are on a pretty good sale and it’s tempting. I’ve been looking at them for a while.I believe HV is for high volume. Has to do with the pole shape/design and how much space is inside the tent. I'd compare the dimensions/volume/height of the tents you're comparing. I have the copper spur HV ul2 for backpacking and love it.
Agree with this ^^^Big Agness recently updated the design of the Copper Spur line within the last month or so, and in doing so dropped the "HV" from the title. The newer ones (Non-HV) have a new proprietary fabric that is supposed to be a touch lighter and more water repellent. My guess would be to offer something comparable to Nemo's OSMO fabric. I may be overlooking a new feature or two, but i believe most other features/design considerations are the same. I have the Copper Spur HV UL2 and it's near identical to the newly re-titled Copper Spur UL 2. I believe the other main design change with the model update are some dimension differences in the XL sizing.
If you don't care to spend the full MSRP of the updated lineup for their hyperbead fabric or the 6% weight reduction, i'd take advantage of the sale on the HV lineup. Great tent, has served me well the last two colorado elk seasons in early September