Archie Comics has been delayed Chilling Adventures Of Sabrina #9 until 2018. The issue was originally solicited for December 2017, but according to an email sent to retailers, it's now being pushed back to 2018. The earliest it would be released would be March if it's included in December's solicits.
In April of this year, Archie CCO and Riverdale showrunner Roberto Aguirre-Sacasa talked to Valnet Inc. Presents Comic Book Resources about getting the series back on schedule after previous delays.
Robert and I are really jamming on the book now, and issue #8, which is the first round of the 'Witch War' — Spellman vs. Spellman — is a few pages from being done, and then it's straight into 9...We're getting our groove back!
The first issue of Sabrina came out in October 2014. After Aguierre-Sacasa gave the above interview, issue #7 and issue #8 came out July 5th and August 23rd, respectively.
Chilling Adventures Of Sabrina #9 may come out sometime in 2018. May.