For each open date with missing meals it takes the active meals on that date's menu and drops any that: don't offer the subscription's portion size; contain one of the customer's allergens; contain a disliked ingredient; or fall outside the customer's category preferences / the subscription's Plan Categories filter. It then fills the day slot by slot, respecting Categories/day quotas, preferring meals that have been ordered least overall (then random) and avoiding repeats until every option has been used. If the Subscription Reorder - Lock Menu module is on and the customer locked a date for that weekday, the same meal is reused for the matching slot when it's still on the menu (and still passes the filters above). Surcharge meals are only used to fill the included surcharge allowance when Allow AutoChoose Included Surcharge Meals? is Yes. The meals are then saved as a meal-selection order (balance first, then card for any extras).