Can't write to a custom Characteristic through EspruinoHub (stuck at "Getting Service")

I can't find a way to write to a custom service/characteristic exposed on the Puck from Node-RED through EspruinoHub.

However:

• Writing from Node-RED to /ble/write/puck/nus/nus_tx through EspruinoHub works
  
• Writing to the custom service/characteristic using nRF Connect app on an Android phone works
  
  

The problem only appears when writing to the custom characteristic through EspruinoHub.
It seems it's not related to Node-RED since the same problem appears also when the MQTT message is published using mosquitto_pub.

Following the guidance in https://www.espruino.com/Puck.js+Node-RED ...:

The format is /ble/write/de:vi:ce:ad:dr/service/characteristic, so you don't have to write to the Nordic UART on Puck.js. You can define your own services and write directly to those.

...and the guidance in http://www.espruino.com/Reference#l_NRF_setServices, this is the code I have on the Puck (first part unrelated (?), but adding for completeness):

setInterval(() =>
    NRF.setAdvertising({
        0xFFFF: String(Math.round(Puck.light() * 1000) / 1000).split(""),
        0xFFFE: String(E.getTemperature()).split(""),
        0xFFFD: String(Puck.getBatteryPercentage()).split("")
    }, { interval: 5000 }), 60000
);

NRF.setServices({
    0xAAAA: {
        0xAAA0: {
            writable: true,
            onWrite: function (evt) {
                LED1.set();
            }
        }
    }
});

And publishing to /ble/write/puck/0000aaaa00001000800000805f9b34fb/0000aaa000001000800000805f9b34fb yields:

<Connect> de:vi:ce:ad:dr: Getting Service...
<Connect> de:vi:ce:ad:dr: Disconnecting due to lack of use (after 30 secs)
<Connect> de:vi:ce:ad:dr: Disconnecting.
<Connect> de:vi:ce:ad:dr: Disconnected

Even extending the CONNECTION_TIMEOUT to 30s and the "getting services" timeout to 15s didn't help.

Any ideas?

Is there some interplay between setAdvertising and setServices?
Am I using the wrong format for specifying service/characteristic ID? (Tried short aaaa, long 0000aaaa00001000800000805f9b34fb, hex 0xaaaa, capitalized, non-capitalized, etc.).

Environment:

• Puck.js 1v90
  
• EspruinoHub up to date
  
• Node-RED 0.15.2
  
• MQTT Broker is hbmqtt built into Home Assistant
  
• All running on the same Raspberry Pi 3