Did you read the article?! Let me quote it for you because it doesn't look like you did: "Spokesman for the Atomic Energy Organization of Iran, Behrouz Kamalvandi, noted the successful testing of the advanced generation of IR-8 centrifuges by injecting uranium hexafluoride (UF6) into them The injection of UF6 is a highly important step and it was carried out according to schedule “the mechanical tests were conducted on the IR-8 centrifuges some three and a half years ago and they were now ready for the next phase, which was the UF6 injection" " This article was written in January 2017, when he says the mechanical tests happened 3.5 years earlier and that they had now been injected with gas as part of their next stage of testing, exactly as I said earlier. Fordow is built much further underground and is near Qom and was not disclosed by Iran, so those are the 3 reasons Fordow is seen as different to Natanz. If you look at the major change in new centrifuges it is their height. The most advanced Urenco centrifuges are 20m+ tall. I read somewhere in Persian about the S series being built specifically for the ease of manufacture/operation reason, if I find it I will post it. Iran disavowed the 300kg stockpile limit after the 3rd response chapter and now has more than 300kg already I think, so that is wrong. JCPOA entails limitations, one of those is not to produce 20% enriched uranium and to purchase the needed fuel from abroad instead. That would expire in due course but Iran didn't waive this requirement yet so I guess it's not a problem. If Russia refuses to sell Iran the needed fuel then obviously they would decide to enrich to 20% again, the fact they didn't shows that they don't think it's necessary yet (to me, to you maybe it is gross negligence and treason, maybe you are right but I don't see evidence for that yet).