OK here it is
journalctl --boot -1 | sed -n -r "/Starting.+Suspend/,/Finished.+Suspend/p"
Sep 06 11:52:30 mj systemd[1]: Starting System Suspend...
Sep 06 11:52:31 mj systemd-sleep[12536]: Suspending system...
Sep 06 11:52:31 mj kernel: PM: suspend entry (deep)