It will not shutdown immediately, because some people rented rigs for longer times, but will shut down completely on Wednesday.
How can you be aware some of people rented rigs for longer periods? What is the communication channel some of them let you know they rented their rigs for a longer period and you should look after them? I don't know many people who would buy huge amount of new company stock or rent a rig for a longer period to mine new alt coin without having a tip from a stock broker or coin owner. If you support private miners you should announce that before people throw their wattage in. 
As I know rented rigs can be directed to alternative stratum address also in case if primary pool dies. I don't see an issue here. Does Bitcoin announces block difficulty ahead so everyone can plan their rentals. LOL