In cPanel 90 up how to set maximum number of recipients per message. It's not properly declared in exim configurations. We wanted to limit it to just 50 recipients.
The limit you are referring to is controlled by Exim setting recipients_max. This setting is not present in the default configurations for Exim that is shipped with the cPanel software bundle. If you wish to set a value for this setting, you would need to add it to the Exim configuration first. This can be done through the Exim Configuration Manager under the Advanced Editor tab. Inside this interface, there is a blue button labeled "Add additional configuration setting" that can be used to generate a line to enter this custom setting.