You should be able to configure the port as Edge, and it should come up as fast as you’re expecting. In the UI this is in System > Switching > Spanning-Tree > CST Port Configuration/Status > Admin Edge Port > EnableThanks for pointing this out. I thought I was nuts, but you're right - it takes at least 10-15 seconds for my network connections to get established.
Here's how I fixed that.
Login to your LB4M. System -> Switching -> Spanning Tree -> Switch Configuration/Status -> 'Disable' Spanning Tree Admin Mode
Note that this may have negative implications, depending upon your network layout. For my setup, there's only one switch so it's all good.
You may then wish to save your changes by going to System -> System -> System Utilities -> Save all applied changes.
That's it. I've tested this on three different machines - all are wired into the same switch and all were seeing the issue that you reported.