If you want to print and the server is offline, and you have selected the Select from a list of last used printers as the Fallback Printing option, a pop-up with a list of printers to choose from is displayed:

Fallback printers list

Select a printer from the list and click Print. The job is printed, and the following message is displayed, after which the job is deleted.

The job was printed at the fallback printer message

If a printer on the list is offline, it will be marked with a grey icon. The online printers are marked as green.

Fallback printer offline - marked grey

The displayed printers can be found in the printers.csv file, stored in Library/Application Support/MyQ/Desktop Client/Users/[username]/printers.csv on the user's Mac. The printers in this file are updated when the MyQ Desktop Client starts, the user logs in to their computer, the Mac changes IP address, and once per day when the user is logged in.