All terrains can be downloaded from this page:
page: To find the terrain that will be in use, refer to the writeup for the event on the Events server here:
here Select FSO
Click on image in main frame. ( should be a picture with Friday Squad Operations spelled out )
This will bring up the details for the current FSO. Scroll down until you see 'Arena Settings'.
Normally, the first item will be the map to be used. In this case ( Fire in the Sky ) it is 'The Slot'.
Find 'AHSLOT2.EXE' on that initial download page I posted, and there ya go. Note, there are no other maps with 'SLOT' in description, so that will be the one.
Good job planning ahead and good luck Friday!