When someone posted a question about this shop, back in April, Suzy64 reported that it was opening Friday (1000-1300) and Saturday (0900-1300) on alternate weekends.
If this pattern has been maintained, the shop should next open on Friday and Saturday of next week (i.e. 1st & 2nd September).
My bosses mum went there last friday and she came back with bag loads. She said that it was absolutely manic in there though so good luck and happy shopping!