While playing with the new BLE READ/WRITE feature for my Playbulb Candles I found that writing was not possible for characteristics which are WriteWithoutResponse only.
I implemented this quick fix which might be useful for others with devices for which they want to write to WriteWithoutResponse characteristics.
Alternatively a more slective option could be possible for a future release, i.e. adding an additional WRITE tag like "ble_write_withoutresponse": true/false