Delivery Cutoff Timer

"Order within 2h 14m for dispatch today." One line on a product page answers the question every shopper is asking — will this get here in time? — with a number that is running out. It changes by itself. At 4:01pm it stops counting and says "Order now for dispatch Monday". On a bank holiday, or across your Christmas shutdown, it names the day you are back. You set the calendar once, and it walks forward to the next day you dispatch, however many closed days are in a row. It runs on your shop's clock, not the shopper's. You store an IANA timezone and every cutoff is computed in it, with the real daylight-saving rules, so your 4pm is 4pm all year. A tab opened at 3:50pm is still right at 4:10, without a reload. What it will not do: there is no evergreen mode and never will be, because a countdown that restarts for each visitor is a lie about your business. With no cutoff set it shows nothing rather than inventing one. It stores nothing about a shopper, sets no cookies and loads no third-party script. It reads correctly out loud: the duration in words for a screen reader, spoken only at thresholds that change what someone would do. Twelve languages. About 2.7 KB of JavaScript.