Another developer came into contact with me and dropped a beautiful early Christmas gift in my lap: A whole slew of sniffed packets dating from alpha all the way to 1.23b. He was working on a private server at the time the game was alive and had captured a lot of data. Unlike Seventh's Umbral sniffs, his character had completed most or all of the content so I have access to packets that a endgame player would see. You'll be seeing a lot more more progress as I have now three to four different characters to compare against and see what SE was doing.

 

I started by finishing off the last few unknown 0x1A_ and 0x19 packets I was looking for.

0x199: Set Grand Company packet. This sets your current allegiance and rank in all three GCs.

0x1A1: Set Has Goobbue Mount packet. This makes the icon in the bottom right appear.

 

I also found some of the linkshell packets and have been able to make the list appear, set the current active LS, and fill the member list!