They should be in centres by the middle of next week but it takes a a fair bit of time to check and sort certificates from 10 -15 different deliveries (you get separate deliveries with their own certificates for each board for GCSE, IGCSE, GCE, EPQ, DIDA, BTEC L2, BTEC L3, FS....) into a different envelope for each of several hundred candidates so don't expect them to be available in the next 10 days, unless the exams officer really has cleared the week to do nothing else - and huge numbers of schools will be running Y11 mocks.