Needs a drop, Proof:

Classifieds at the time -> http://imgur.com/pXa3a90

x1 at 14 keys 4 ref

x1 at 14 keys 7 ref

Sellers below 15 keys:

http://www.tf2outpost.com/trade/20719910 - 14

http://www.tf2outpost.com/trade/20377346 - 14

http://www.tf2outpost.com/trade/20761569 - 14 keys 7 ref

Sellers at 15:

http://www.tf2outpost.com/trade/20672876 - 5 days

http://www.tf2outpost.com/trade/20688152 - 4 days

http://www.tf2outpost.com/trade/20775551 - 1 day

http://www.tf2outpost.com/trade/20818363 - 13 hours

http://www.tf2outpost.com/trade/20805663 - 21 hours

http://www.tf2outpost.com/trade/20612017 - 6 days

Conclusion: Still many sellers at 15 keys but sellers at 14 key sellers are starting to appear. Some at 15 keys are young, so i'm keeping 15 keys in the range and some sellers at 14 keys, 4 ref and 14 keys, 7 ref thus a range is needed.