Unfortunately we have no plans to release the rest of the series at the moment - we have to buy the rights from the publisher for each title and the demand from our customers is not currently high enough to justify the costs. We apologise for the fact that this means the set is incomplete and are constantly reassessing the situation to see if we can offer more of the books.
We apologise for any disappointment caused.
BCA Customer Support
So those who wanted the entire collection will be disappointed and it also when it becomes more common knowledge lower the over inflated prices theses books fetch on the 2nd hand market.