All data from https://github.com/vradarserver/standing-data/
JSON data is accessible for each callsign at an URL like this:
https://vrs-standing-data.adsb.lol/routes/IT/ITY110.json
Additionally, full csv files are available at:
Data is updated every hour from upstream.
Please submit corrections to aircraft, airlines, airports and routes via the SDM site: https://sdm.virtualradarserver.co.uk/Edit