First, thanks for a very quick reply and yes, I’ve tried to re-add a pair of TRVs and did factory reset on them, didn’t help. My assumption that this is related to a 1.1.5 firmware version of TRVs, because according to 【TRVZB】Firmware Changelog this feature was added in version 1.2.1, but I’m wondering why I can’t update firmware version for TRVs.