Bulk Action
One middleware response can contain several updates, delimited with the '&' sign. For example, to set 'cconfirmed' property to '1', 'phone' field to '123456' and make activity unscheduled, the 'data' node should contain the following string:
#params?cconfirmed=1&phone=123456&action=unschedule_activity
Note: The total length of the 'data' field cannot exceed 255 characters.
If a submitted 'data' value exceeds the limit, it can be correctly processed but will be truncated in the database.