Here in Serbia this cellphone is not cheap, its expensive. And its a dump idea to stop suporting. Its my think....
Eh it's still expensive like right now? If so then wow. In my country, you can buy Z1 as cheap as a low mid-range phone. (Sony pricing strategy really does suck)
Like others said Z1 is old and passed the 18 months promised support time from Sony. Yet we still receive bug fix and enhancement firmware like recent 236. I think we should be graceful for that since it's way better than other equivalent from other brands. Have you seen any Snapdragon 800 phone got M yet?
Also I don't know why many of you think not getting M is a stop support from Sony while we still indeed receive newer firmware build on 5.1.1. I think support means in the end you get the stable stuff not the newest one. Otherwise, after M people will demand N then O then P etc. for Z1 just for the sake that Z1 may have the spec to run it. And let's face it: even if Sony want to, they probably don't have enough resource to support Z1 (not with their current financial status). Supporting Z1 bring no benefit to Sony.
One more thing: if you look at the Z1 Update History on PTCRB, you'll see Sony did a fantastic job supporting this phone up until now. And even if we, by any chance, got the M, I'm sure it will feel like nothing because we won't get any new features (those are saved for latter Z series) - not to mention a new base firmware potentially bring lots of bugs.
==> I myself would be happy if they just provide me a super polished 5.1.1 firmware with no bugs at all.