This is very frustrating issue. It’s fixable, but you must manually edit the pln file creted by simbrief with a text editor.
Add the following right below line starting with DepartureName. Edit as necessary to match airport.
<DeparturePosition>GATE B 8 PARKING NONE</DeparturePosition>
Then delete the following two lines from the first ATC waypoint.
<RunwayNumberFP>24</RunwayNumberFP>
<RunwayDesignatorFP>LEFT</RunwayDesignatorFP>
Then load the plan.
If there’s an easier way, please share.
Maybe Navigraph/Simbrief can fix this on their end somehow.