Get a list of probes tagged with system-ipv6-works and save it on v6probes.clean:
$ ripe-atlas probes --status 1 --tag system-ipv6-works --limit 3000 > v6probes
$ cat v6probes | grep Connected > v6probes.clean
The --tag argument is part of a PR that has been merged into Magellan but that's not released yet.
Run the parse_probes.py script (you can find it within this gist) to filter probes and to consider only max 5 probes for each source ASN among those whose ASN_v4 and ASN_v6 match [1]. The script prints a list of RIPE Atlas Tools (Magellan) commands to execute in order to start measurements (you need an API key in ~/.atlas/create).