The 29th of May was the last day they could have appealed to CAS (after the FIFA ruling, we were given 21 days to appeal to CAS) We did not, as far as I can see after a fairly thorough search, appeal it in time.
https://www.fifa.com/about-fifa/who-we-are/news/fifa-appeal-committee-passes-decision-on-appeal-lodged-by-chelsea-fc
here is the CAS website, with list of hearings, we are not on it
https://www.tas-cas.org/en/general-information/news-detail/article/list-of-hearings.html
I think this is their reasoning:
Chelsea might accept transfer ban in bid to see it reduced
https://metro.co.uk/2019/05/23/chelsea-might-accept-transfer-ban-bid-see-reduced-9658111/