I have also seen a number of new Soldiers explore the limits of their facial hair--specifically sideburns.
Sideburns may not be flared; the base of the sideburn will be a clean shaven, horizontal line. Sideburns will not extend below the lowest part of the exterior ear opening.
We simply say it is not a good idea to have the First Sergeant squint at you trying to determine if your sideburn conforms to the standard and consider having it terminate at the top of your inner-ear opening.