Hard to say. Sounds like a good question for the HR dept. For myself I believe it is at least a two week process. You might also ask if it will require a doctors recommendation or letter to qualify. Concussion can be beast to cope with and I am sorry you are experiencing these challenges.
49, Male Married, PCS since June 2012, headaches, Back pain, neck pain, attention deficit, concentration deficit, processing speed deficit, verbal memory deficit, PTSD, fatigue, tinutitus, tremors.
To see the divine in the moment.