Hi,
Refer to other friend's experiences like this:
It seems both XEP & EP AOR are coming from CIO but those are produced from different stages in different times. XEP AOR is the same as EP AOR but it has one extera X.
XEP AOR means: assessing of the file finished, file is complete, they accepted that and it is ready to proceed to the visa office but they still didn't add it to their ECAS system and it is not track-able online.
EP AOR means: File already entered in their ECAS system and it is track-able online now and after that file will transfer to local visa office.
These days, it will take about 60 days, CIO assess a package and send XEP but I don't know why it will take a long 30 extra days to enter the file into ECAS system?! Maybe there are extra procedures between those steps and they are hide from our eyes?! ???