When send standby all columns is associated with a replication definition, Replication Server sends whatever data it receives from the Replication Agent using the original column names and datatypes. The replication definition is used only to find the primary key.
If schema changes do not involve dropping all primary key columns in the replication definition with the send standby all columns clause, the scenario is the same as one with no replication definition. All options of alter table are supported, and no action is required in the Replication Server.
You can alter the replication definition at any time to drop all primary keys in the replication definition with the send standby all columns clause, and add the new primary key columns to the replication definition before you alter the primary table.