Hey cow: does the API not return the fair basis, er, suffix, all the time?
I note a corporate booking showing up as, say KNA4A2FL/8N02 and LNA2A0FL/8N02, but some cash/buddy faira being GNA4A2CO, SNA0A2CO, without the /CFC that my associates invoice shows. (The cash fair receipt doesn't have the suffix, and I did use both my last name and theirs when searching your tool. It being different is a interesting observation for the internal systems as much as yours)
This may be a pathological situation, I grant.