It really depends on the pending action, I'd open a ticket with support, to verify. Some of them you have to open the ruby console and you could cause problems if something goes wrong.
I also suggest contacting VM Support as sjesse says but just out of curiosity. How many Appvolumes managers do you have and how many users are concurrently using the environment?
There are a few things to tweak but thing is that you need to be very careful with those settings and you might end up with more errors than you have already.
If you do have more than 1 Appvolumes manager behind a loadbalancer cluster one suggestion could be to restarte them one by one. Also, it might be that tomorrow all actions are gone because it can process them in the night.