I have been running K and Ka band - highway mode enabled, full time since I got my unit back a few weeks ago. Pretty much right away I noticed a difference in K band, but was hard to nail it down. I notice it usually alerts in the same locations as before, out in desert at some factory, driving by the local Target store, same unknown K source on the freeway every day going to work.
So I think I have figured this out. It alerts to the same distance, but the RAMP up is now more tame. I went spinning round in the local Target parking lot - a pretty huge lot that I originally tested my Redline with last year. The difference is that it does not go full tilt when I am in pointing at / close proximity to the door openers as it used to. Off axis is the same, but a lower threshold alert. This is fine with me, as long as it has the long range as it did before.
Now I wonder if Ka ramp was tweaked. Not enough long range encounters to determine that - will be a few more weeks before I do another desert run to find out.