Series 1 doesn't show option to update to OS 5
I have a Series 1 (A1553) watch and when I go to General - Software Update on my iPhone is says 4.3.2 is up-to-date. My iPhone 7 is running 12.1.3. I've tried restarting both devices, as well as unpairing and then repairing and restoring the watch. No change.
Anyone else having this issue?
Apple Watch