I'm having trouble upgrading -- PayPal has a 20% upgrade limit
Unfortunately PayPal does have limitations with only 20% increase in pricing allowed (to avoid fraud).
The best workaround is to cancel your current subscription by emailing us at firstname.lastname@example.org, and then re-subscribe to another plan using the payment option directly on our site. As long as you do this immediate after cancelling, your trackers shouldn't lose any data.
To ensure this is the case, visit the My Tracks page to resume any paused trackers immediately after upgrading, so that you don't lose any data. Please contact us at email@example.com or file a support ticket if you run into any issues.