I believe my system is affected by this issue. I have tried the workaround posted by Jayson Willson. It seems to help sometimes, but I believe there is still a race condition. Most often, the system waits for me to enter a passphrase. I have seen it wait for several minutes without problem. However, sometimes it drops into emergency mode within seconds of prompting for the luks passphrase.
Also, perhaps related, the earlier system prompted a second time if the passphrase entered was incorrect. With systemd it seems there is no second chance, only a broken emergency mode and necessary reboot.