I've been speaking to my contacts at Big K today and they've told me that there will be supply problems on their 15kg bags of restaurant grade charcoal and they're unsure of when this will be resolved.
The 15kg bags from Big K are filled with their ACH15 charcoal which is their hottest & longest burning charcoal and I've found it to be very clean burning compared to other charcoals I've used and it comes in large chunks which makes it great for smoking.
They do still have large stocks of their 12kg bags which is made from a slightly different hardwood charcoal. Big K are sending me a few bags of this different charcoal and I'll let everyone know my thoughts after giving it a try. I'll also bring a bag of it to MIM.
If you've been using the 15kg bags and want to keep on using it this year, I'd suggest stocking up now whilst it's still available.