From Alan Causer
If a student enrols, gets a card, and puts money on same day, their usercode will be created early next day (usually between 8am and 10am on heavy enrolment days) but the money won’t appear to be available for printing for a further day.
If they put money on after their usercode is created but same day, it will be available as usual, within 20 minutes.
Students can be manually enabled if they are in the former category. (by Alan or Michele)