The customer sought assistance with the GNMI stream on_change feature on PTX EVO 23.4R2-S1.6

As per our documentation, the 'ON_CHANGE' option is not supported. This is because it is a dynamic field that requires streaming. The leaf /components/component/optical-channel/state/input-power/instant has been supported since version 22.3, and the container /components/component/optical-channel/ is supported only for ZR/ZR+ optics.