v3 local API?

I would like to fetch the electricity sensor readings at a greater frequency than used to publish to the online dashboard (which I believe is every 15 minutes).

I know that the Fluksometer v2 used to support a local REST API to fetch sensor data for the last minute at second intervals.

I also know that V3 publishes the same data via MQTT which is great if you have an MQTT client but I dont (I am using Fibaro Home Center 2 and Lua to collect data from other devices via REST APIs and the Fibaro predates MQTT so doesnt support it, without having to build a "man in the middle" type solution with a Raspberry Pi or similar.

So my question is: Is the local REST API still available under V3 but disabled? and if so, what would I need to do to enable/access it? Thanks for your help.