Refill seven landed on day 26 instead of day 21, and the shipping window ate four days I hadn't budgeted for. I keep a tab that tracks cost per week instead of cost per order, because the per-order number is useless once the quantity changes. Last three refills: 41, 38, 44 dollars per week. The middle one was cheapest only because I caught a stock window and skipped expedited shipping.
Stock anxiety is the actual driver here. I log when each source goes dark and when it reappears, and my notes show a rough 9–14 day gap in availability around the first week of each month. That pattern has been more useful to me than any promo email.
Curious whether anyone else budgets by week rather than by order. I want to know if 44 is just what this looks like now, or if I'm simply bad at timing my reorders.