BBB trick
There is very serious organization "Better Business Bureau"
They can to send your compliant directly to Bittrex office
And they answer! And BBB forward their answer for you
You can write to BBB all your problems include verification issues, disabled account, email blocking, blocking in support with "Your account is under review message"
It's working! Many people solve their problems that way
Read about BBB here https://en.wikipedia.org/wiki/Better_Business_Bureau

Link https://www.bbb.org/northwest/business-reviews/virtual-currency/bittrex-inc-in-bellevue-wa-1000048938

Push "Submit A Compliant"
Then "File a Complaint"
BBB: Qualification Questions
Select all NO
And click "Proceed to Compliant Form"
Neatly fill all the fields
Check "BBB may contact me via email."
And click "next"
Finally on the next pages you should explain the situation in as much detail as possible
I assure you that the BBB will send your complaint to them, receive an answer from them and forward you their answer
DO NOT FORGET TO INCLUDE YOUR MAIN TICKET NUMBER IN THE COMPLIANT
ALSO YOU CAN USE 2FA & BBB TRICK SAME TIME!
In practice people received an answer from the bbb at the same time as an answer to the ticket from Bittrex
It took 2 days maximum at this time

Q: Will BBB trick work for "Under review"?

A: Bittrex will get your compliant
Bittrex will answer you
If you want to receive answer from they, in this case this method works
You may continue dialog with Bittrex after first answer
You may try to compel them give an answer on "Why you disabled my acc?"

BBB will forward your compliants again and again to Bittrex and maintain a dialog with you and them