10.2 Ineligibility  for Presence, Use or Attempted Use , or Possession of a Prohibited Substance  or Prohibited Method   The period of Ineligibility  for a violation of Article 2.1, 2.2 or 2.6 shall be as follows, subject to potential elimination, reduction or suspension pursuant to Article 10.5, 10.6 or 10.7:   10.2.1   The period of Ineligibility , subject to Article 10.2.4,  shall be four (4) years where:   36  [Comment to Article 8.4: In some cases, the combined cost of holding a hearing in the first instance at the international or national level, then rehearing the case de novo before CAS can be very substantial.