Huh, didn't know that was possible.
I gather you can modify it though? That's what made me go for it, I get Pact (coffee) on a subscription-ish (auto-order more apt I suppose) and I'm always changing that.
Went for a relatively small amount over a long time frame anyway though, figure I can always get more (more easily than less) if required.
Anyway, I kept trying, and it just suddenly worked. Huel say they didn't change anything their end, so :shrug: