As followed in this thread:

http://www.swtor.com/community/showthread.php?t=970302

 

I have a large stack of Completed Bounty Contracts from years of doing this event prior to 6.0. Onslaught brought a lot of new appreciated quality of life features, including the new ability, at the appropriate vendor, to convert character-bound Dantooine Surveyor Notes into legacy bound Dantooine Surveyor Tokens, which can then be transferred and used on other characters. This ability was already present with other event currencies, like Gree event Gray Helix Components and Rakghoul DNA canisters, but it looks like Gree and Rakghoul currencies were updated to the new system as well.

 

Completed Bounty Contracts, or CBCs as I will call them from now on, were unique because they weren't bound at all. They could be traded or sold on the GTN. I don't care much that these won't be able to be sold on the GTN anymore, I always kept them for myself anyway. However, you cannot use any old, pre-6.0, CBCs to buy the new legacy bound Bounty Contract Tokens on the BBA vendor. You cannot use them for anything, actually. In that thread, the poster Rusah said they got CS to convert their CBC to the new version, but I've submitted three tickets now over 6 days and have been told by CS I have to submit a bug report.

 

So, here is my bug report.

 

Pre-6.0 Completed Bounty Contracts cannot be used at any BBA vendor. They either need to be converted into the new Completed Contract Tokens (which are legacy bound) or whatever the new version of the CBCs are.

I have quite few myself, updating of these I didn't know about these are just sitting in the storage on one of my alts, will there be a game wide fix for these or does one contact CS on a case by case basis

Waiting for the devs now.

workaround found!

http://www.swtor.com/community/showthread.php?p=9786361#post9786361

yep same here