If all the Archiver roles fail over to the same standby server at the same time, you can assign archiving priorities to the roles to avoid overloading the server.
What you should know
NOTE: At any point in time on a given server, only the Archiver roles with the highest archiving priority will be able to archive. The archiving priority only affects archiving. Having a lower archiving priority does not prevent a failed over Archiver role from performing its command and control functions.