Well it seems that this might actually be related to timezone database files. My timezone is America/Indianapolis but I noticed when I set the timezone to America/New_York or UTC that this problem doesn't happen
$ TZ=America/Indianapolis date -d "now - 9001 days" date: invalid date ‘now - 9001 days’ $ TZ=America/New_York date -d "now - 9001 days" Thu 05 Sep 1996 07:05:55 PM EDT $ TZ=UTC date -d "now - 9001 days" Thu 05 Sep 1996 11:05:59 PM UTC $ TZ=America/Metlakatla date -d "now - 9001 days" date: invalid date ‘now - 9001 days’ $ I found that last one after trying a for loop in /usr/share/zoneinfo/America So I'm not sure if this is a problem with coreutils or a change in the zoneinfo database. Any ideas? Mark