My 830 was unlocked, too; but it also said "..We're working with your provider.." so while the phone is eligible, it hasn't been sent W10, yet. To-date, I don't think my former provider has still even sent W10 over the air.
I got the Windows 10 update by using the Windows Insider app.
Even when it's network unlocked (you can use it on any compatible network), you're still running the ROM from that original network (unless you've flashed it) and they are still in charge of pushing those OS updates, unless you bypass it with something like Windows insider.