Ok, I think I've read too many threads and got myself mixed up a bit.
If you get a z1 and update the software -- is that the same as a z2?
And if you get the z1 + update the software, can you use the 2-wire bypass still?
Apologies if this is already answered somewhere, but there's so many threads it's hard to grok the "final" answer.
thanks in advance.