Gang -
I can't speak for the entire world here, but at least here in the US this has been offered as a free upgrade. I know this forum (more than any other that I've seen) has really gone on about the "notchy focus" deal. This is a design feature in that we use metal on metal - brass disk on an aluminum helicoid - without gobs of grease like competitors.
The reason for this is that it allows uniform performance in all conditions. E.g. heavily lubricated focus systems congeal in cold temperatures and become very stiff, in hot conditions these systems often run too fast with a lot of "over travel" problems. Also, since these products are built to last (and I do see 20-30 year old Leitz Trinovids regularly being used at nearly every show I attend!) so without grease to collect dirt over the years this system will continue to work over the long haul. Heavily greased systems will turn to sludge.
The HD focus system, as I understand is not really all that different from the BR and the upgrade consists of a series of teflon washers placed at strategic points. As to the 3.5 month turn around I can't begin to address that. Likely has something to do with the timing, and of course when a product is sent to Leica USA, then to Leica Germany, back to USA, then to consumer you will lose some time as well, but who knows I'd have to look into specifics of this particular situation to know.
The good news is I believe these upgrades are now done in house here in the US. So no need to send over to Germany. Further from all I've heard over the past 3 months from consumers, Leica USA, and on the forums, binocular turnarounds right now seem to be running near 2 weeks & less here in the US. As a liason to the company working consumer shows, I ALWAYS hear about it if repair times start getting long! ;p
Regarding the question about all of the repair techs being on holidays, it is certainly a possibility. It's a very foreign concept to us here in the US, but indeed when holidays come in sumer, it seems half of Europe shuts off the lights, and locks the doors for a month at a whack!
Hopefully this helps!
Jeff