Seconding this, have been unable to play Siege since it's release last Saturday.
Summary: Siege queue finishes, the game loads in, and then it freezes and kicks me back to the main menu
How to Reproduce: Simply queue for any siege match
Version: 1.0.3, will test on 1.0.4 and update this message
Computer Specs:
OS: Windows 10
GPU: GTX 2070 TI
CPU: AMD 2600X
RAM: 16GB
Motherboard: ROG STRIX B450-F GAMING (AM4)
Storage Device (HDD/SSD): Intel 660p