Comichron has their sales estimates for November 2018 and as it stands the debut issue of The Green Lantern came in as the second highest selling book of the month.  Uncanny X-Men #1 took the top spot but the first issue of the new series by Grant Morrison and Liam Sharp was DC’s biggest seller with 113,651 copies sold.  This doesn’t take into account digital sales, but just based on the paper edition numbers it is a strong start for the new book.

Source: Comichron