On their Discord, a dev told me they will “fix the tooltip”.
When I dig into my account settings under Active Subscriptions, I can see the real date too - I just hadn’t looked there before and trusted the top-level display.
What puzzles me is that they only plan to fix the tooltip rather than actually show the billing cycle.
Given their strict “no refunds” policy, I can’t help but suspect some bad faith here.
If it were truly just a mistake, I’d expect something along the lines of: “Oh, yes, we’ll fix this misleading display - and of course, here’s your refund.”