This looks like a glitch, as Turkish is releasing at least 8 Business Class seats for most summer dates, from now until the end of August for award bookings. This availability will not last long, so if you’re looking for summer travel, BOOK NOW!
Here’s a search for a direct flight from Toronto to Istanbul for eight people. The green/blue means there’s Business Class availability:
And here’s a search from Chicago to Istanbul for eight passengers as well:
As a reminder, Aeroplan does not levy fuel surcharges on Turkish, and their Business Class product is fantastic. For example, a one-way for eight people in Business will yield a total tax liability of $433.28, which is only $54.16 per person!
Availability from Istanbul is also fantastic, for example, the following is for eight people from Istanbul to Toronto:
This won’t last long, so book it while you still can!