Quote from the 1.2 Legacy Patch notes
http://www.swtor.com/patchnotes/1.2.0/legacy
"Players can now send multiple companion characters on a mission granted by a Mission Discovery if the player had more than one of that Mission Discovery."
I found the exact opposite to be true. Now I can't even learn a crafting mission if there is the same mission being run by a companion. It's going to take forever to get through the pile of missions I've saved up for 1.2.
I just want to say a big thank you to Bioware for allowing players the grace period. Purolator "Delayed in transit due to a missed connection" my CE 2 times now, and it looks like I will only receive it Wednesday at the earliest.