Z-wave battery devices generally fall into two groups. Sensors, which only wake on an interval (usually 12 hours) to take configurations, they send sensor readings at any time as configured. Or FLIRS devices which can accept commands and wake every 60 seconds. The only "polling" done with zwave is typically for older non-plus mains powered devices AFAIK.
Zigbee battery devices are different, I am not sure how they work exactly but the few sensors I have seem to be always awake, I can send them configurations or refresh and they respond fairly quick. Not sure if there is a difference in Zigbee sensors vs devices that take commands like your TRV controller.
Here is better info on Zigbee devices: Discussion about battery-powered z-wave/zigbee devices - #21 by hubitrep