If the network is not available when fstab is parsed - then the share will not be mounted but is likely to cause a system hang for 120s.
Please see the mount unit samples topic in the Tutorials section on how to properly mount a samba share or you can use the utility script using gio.
→ [root tip] [Utility Script] GIO mount samba share
→ [root tip] [How To] systemd mount unit samples
→ [root tip] [How To] Basic Samba Setup and Troubleshooting