update

As you may have read earlier, I can talk with my hands. I took the proficiency test and got my results back today. I fell in the Advanced Plus range. Which means that there are only two levels higher than what I scored, and I'm almost at the Superior level, but not quite.  (scoring scale and full explanations available online here.) 

Here are some highlights from the notes of my test results:

"Able to have a shared conversation with good, spontaneous elaboration for both

social and work topics."

"Very clear production of signs at a normal/near native-like rate."

"Very good use of many sign language grammatical features including use of space, use of role shifts, sign verb movement direction, repetition of sign verb movement, word order flexibility, and classifiers."

"Very good comprehension of sign language produced at a normal rate, with no repetition or rephrasing necessary." 

Overall, I'm extremely happy with the results of this test. The interpreting program that I'm trying to get into told me that they usually look for candidates who score at least in the Intermediate range, but preferably higher. I scored higher. Now I just have to wait to hear back from the interpreting program to see if they want me.