Who's best to make updates?

If you're just going to try to convert the queries to the old timeboxing style, then anyone that's familiar with that.  If you'd like to use the reportupdater timeboxing, probably one of us would have to at least show it to you.  Here's an example that's running for the visual editor data:

https://github.com/wikimedia/analytics-limn-edit-data/blob/master/edit/config.yaml#L55

The tradeoff is that working with us might be slower.