Hi Jonatha,
It was nice meeting you last time and you are the right person to catch for this 
I am also facing the same issue. We are using working on IS 9.10 but using 9.12 Designer.(this was not giving any issues in previous versions)
While saving the doc publishable doc in the designer, it’s not allowing me to set the encoding type as “Protocol Buffer”; Automatically it’s changing it to “IData” and when I tried to reverse the changes by using 9.10 designer; it’s not at all allowing me to update the doc.
Please let me know if this issue is already addressed. I am attaching the diagnostic data fro more information.
diagnostics_b2b9isdev01.isus.emc.com_5555_20170614093621.zip (873 KB)
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