As an XO player, i consider “the frontlines” to be the part of the map where the fighting is the most thickest (atleast 5-10 xenos and 20-40 marines present), areas adjacent to it “the flanks”, and everywhere else to be “the backlines”
I think the report is completely bull. Like how was that considered “frontlining” what was staff thinking?? CL was literally just a few tiles away from the FOB. Do we have to fear RP and fucking freeze up in shock 
everytime we see a xeno as a civie and not fight back?
IMO any role should be able to go wherever they want as long as they have permission from the XO/CO, because i think it could create alot of fun scenarios.