It would be really helpful if Mormons would stop trying to force Christianity into their restorationist 'prophet/apostle matrix' or whatever, as though any actually-existing church should have to fit into the made-up requirements for being the true Church that Mormonism has made up to place itself in a higher position than the lowly Catholic, Orthodox, or Protestant churches.
For Orthodox Christians, we have the same prophets and apostles as you'll find in the scriptures, since we are Christians. There is no indication anywhere in early Christianity itself that there
needed to be a continuing line of apostles and prophets in order to testify to the validity of the Church or whatever; in fact, the more common opinion was and is that the age of
public revelation ended with the death of the last apostle, and what we have received since is to strengthen us in the faith that was
once delivered to the saints. ('Saints' in this context meaning Christians, not Mormons.) This is through the guidance of the Holy Spirit -- the One God Who also guided our fathers and masters the apostles and the disciples into all truth, including in the writing of the Holy Scriptures -- but it is not anything
new, so it's not 'revelation' in the sense that Mormons would use that word when talking about, say, the D&C. This is why you don't see any additions to the scriptures since a long time ago in Eastern Christianity, even though the Christian East (unlike the Western churches) never officially closed its canon. There's not a sense of needing to add anything to what we have received.
The people who came with something new (e.g., Marcion, Montanus and his prophetesses Priscilla and Maximilla, Sabellius, Mohammed, Joseph Smith, etc.) are condemned for having done so, as they did not hold to the faith that was once delivered to the saints, nor sought to strengthen themselves and others in it, but instead came with their own foreign messages which they said they received from God, but which did not comport with the Old and New Testaments, which is the test according to the ancient witness of actual Christian saints such as
St. Jerome (writing below to his friend Marcella in 385, after the Montanists had begun pestering the Christians in Rome):
If, then, the apostle Peter, upon whom the Lord has founded the Church, has expressly said that the prophecy and promise of the Lord were then and there fulfilled, how can we claim another fulfilment for ourselves? If the Montanists reply that Philip's four daughters prophesied at a later date, and that a prophet is mentioned named Agabus, and that in the partition of the spirit, prophets are spoken of as well as apostles, teachers and others, and that Paul himself prophesied many things concerning heresies still future, and the end of the world; we tell them that we do not so much reject prophecy— for this is attested by the passion of the Lord — as refuse to receive prophets whose utterances fail to accord with the Scriptures old and new.