Stopping grading won't help anything. Instead it will create the backlog as soon as they open back up again.
Hypothetical numbers:
Each month CGC does 100,000 cards. If they stop for 4 months like PSA where do those cards go? To PSA/BGS some other company? Sure some will. What about the die hard CGC fans that don't want to have it slabbed by some other company? So we'll say 25k each month disappear to the other guys.
So after 4 months CGC is caught up again...doors open...what do you think will happen to the 75,000 * 4 that have been sitting waiting to submit? Guess what??? CGC times explode again...however now we have 300,000 + the extra 100,000 for the month.
I You guys.