This site states this directly right below its pricing tiers: every package above is a one-time fee. Confirm your final total, including shipping, at checkout.
Naming this explicitly — rather than leaving it ambiguous — is worth crediting as a clear, upfront statement about billing structure before you commit to a purchase.
Confirm the per-bottle price for your chosen package, whether shipping is free or added, and that no recurring charge appears anywhere in the checkout flow before you submit payment.