The New York-based community said on September 16 it had learned that the 20-year sentences against the five men and two women had been reduced.
"The only oral news which I have received from Iran is that the lawyers representing the seven Baha'i leaders were informed orally on September 15 that the 20-year jail terms have now been reduced to 10 years," Diane Ala'i, the community's representative to the United Nations in Geneva, told Radio Farda.
Ala'i said she is not overly optimistic as the judiciary system in Iran is inefficient and unpredictable.
"These seven detainees never had a file, they have never been informed officially -- even their 20-year jail terms were [communicated] also orally," she said. "In Iran judiciary proceedings generally are not clear and efficient."
But she expressed hope that an appeals trial will be held officially in the presence of lawyers.
Fariba Kamalabadi, Jamaluddin Khanjani, Afif Naeemi, Saeed Rezai, Mahvash Sabet, Behrouz Tavakoli, and Vahid Tizfahm were sentenced on August 8 after being found guilty of "espionage," "acting against national security," and being "enemies of God."
Ala'i strongly rejects these allegations, saying they were arrested because of their faith.
"I am sure if there is a fair trail these seven prisoners will be freed," she told RFE/RL.
Some 300,000 Baha'is live in Iran, making it one of the largest Baha'i communities in the world. Iran is where the religion was founded in the 19th century.
But the Iranian government does not officially recognize the religion and severe limitations are imposed on its followers, including a ban from attending university.
The government has also sanctioned the destruction of Baha'i holy sites, including the former residence of one of the religion's prophets in Shiraz.