I agree with everything you just said. The fact the 3D was such a disappointment to Sprint in terms of sales, I agree with you that update priority and resources in general tend to go first to where the most customers are. So if the 3D never sold as well as they wanted, and doesn't have a lot of subscribers, then when push comes to shove they will be further down the line as Sprint wants to kill the most birds with one stone so to speak, and make the most people happy in the smallest number of steps.
I hope you're right and that June is the late end of when we'll get the update, and as you point out that would already be at least 1 full quarter later then when it was initially promised. But being as it's already May and we don't even have a leaked Sprint version of this update yet, time is running out to be able to deliver a solid update with minimal bugs in just under 2 months if we are to truly get it by end of June.
I'm also hoping for a June release, however knowing this is such a big update (not simply an incremental update) and how much goes into making it work as smooth as possible without problems, I won't be shocked if it drags out into Q3 sometime.
So I'll be pleasantly surprised to see it by June (end of Q2), however with how this has been pushed back so far and seeing how this device never got much traction, I won't get my hopes of for Q2 and wouldn't be shocked if we don't see it until sometime in Q3.
Regardless, as you point out we are STILL getting ICS, that isn't in question. The only question is when....