A search on the forum would reveal that non-supporters only get limited history from Strava in that way (API connection).
You can however request your full history from Strava. They will provide a link that you can insert on the Settings page under your Strava connection. And then you will have your full history, with 2 advantages:
- You don’t need to subscribe to Intervals
- You can do with that Strava data anything you want, because the download has your original files and they are ‘yours’. The data synced from Strava through the API connection, is a Strava modified file. And Strava considers that is 'their ’ data. Meaning that you can’t use Intervals to forward it through the API because that’s an infringement of Strava’s policy.
- If you use Intervals on regular bases, the sync with Strava will remain active. After a period of inactivity on Intervals, the sync will be paused to save on API calls, which are limited by Strava. That’s to protect Intervals users that are regularly active.