Exporting all data from Influx Cloud 3

I got started with Influx Cloud 3, but I’m now finding it prohibitively expensive to run for my personal project, and want to migrate to self-hosted Influx OSS 1.0.

What’s the best way to export all my data from the cloud instance? influx backup is not supported, and I’ve gone through all the cloud docs I can find, and can’t find any reference to this.