Under the map exploit on Iberian Offensive Conquest

I can't tell you exactly where and I dont have a screen shot of it.  But was playing conquest on Iberian Offensive and noticed players prone crawling out of the stairs on the C flag.  We just could not seem to keep them off that flag and everytime I went back there someone would prone crawl out of that same set of stairs.  I imagine they had a spawn beacon there.  This needs addressed.