Supplemental claim stuck at regional office

I submitted my supplemental claim June 10 and for some reason they thought I wanted an informal conference, which doesn't make much sense but oh well. I only submitted new evidence for two conditions, migraines and IBS. I had a HLR done for both of the conditions where a clear unmistakable error was made for IBS giving me 10% and there was no increase for migraines, but I have 0% service connection. On August 25, a request was sent to the regional office to correct my supplemental claim. It is currently waiting in the national work queue. So I have a few questions for anyone that might be able to help.

1. How long should I expect my claim to be sitting at the regional office?
2. Has anything like this happened to anyone?
3. My original C&P exam was completed October of last year, and the examiner did not document anything correctly. The new and relevant evidence that I submitted does not match the examination notes. Should I expect to do another