Possibly autofs is trying to mount the drives before the network comes up and is available?
This has been an ongoing issue using NFS or samba and NetworkManager. It seems that NetworkManager tells systemd that the network is up before it's actually ready, and systemd fires off other services that use the network too early.
You can try starting the NetworkManager-wait-online service and see if it fixes your issue.
systemctl enable NetworkManager-wait-online.service