If, this was the first test by ASAP with the sample taken by ASAP after self-enrolling, then it is protected by limited-use. If the Soldier took a unit urinalysis, had an “OH SHIT” moment, and then self-enrolled before the results came back, then no, it is not covered by limited use policy. Also, the limited use only applies to the first test after enrolling. If the Soldier tests hot again, after the period of time the drugs detected in the limited use test should be out of their system, then they are free game for the command to punish as they see fit.
As far as type of separation if the Soldier is chaptered for misconduct: Normally for one drug hot, with no other misconduct, more than likely a General – Under Honorable conditions. If however, there is other misconduct, then the command could look to separate with an Other Than Honorable. I have seen units separate a Soldier with a Other Than Honorable for only one drug hot with no other misconduct. It’s up to the chain of command on what they recommend. Normally though, since a Other Than Honorable automatically entitles a Soldier to an administrative separation board, the command will go for a General – Under Honorable Conditions to get the Soldier separated quicker.