Zelensky has confirmed that he is in fact going to be firing Zaluzhny confirming that the recent speculation was in fact true.
RIA Novosti (Original article in Russian) is also saying that he is going to be an ambassador to the UK in the near future:
Commander-in-Chief of the Armed Forces of Ukraine Valery Zaluzhny agreed to become ambassador to the UK, said Verkhovna Rada deputy Yevgeny Shevchenko in an interview with the director of the Ukrainian Institute of Global Strategies Vadim Karasev, published on his YouTube channel.
It seems to be legit actually, I found this article by gazeta.ru, which Wikipedia classifies as Russian state-controlled media claiming the same thing. In the article is this quote:
If someone here actually speaks Russian feel free to correct me though.