Hi, we have tested it. When outlook save the email, if the sender is an account existed in outlook, the message will be marked as self-sent, so when you click reply all, from will not be included in the destinations, however, when you use EAGetMail save the email, EAGetMail doesn't know if sender is an account existed in local outlook, so when you click reply all, from will be included in the destinations.
That is not a bug or limit.