An intensive course of sādhanā (spiritual practice) prescribed for the Upāśaka (lay follower); no exceptions like rājābhiyoga (king's order) etc., are allowed in such course; the total period of this course is five and a half years.
upāsakāḥ- śrāvakāsteṣāṃ pratimāḥ- pratijñāḥ abhigraharūpāḥ upāsakapratimāḥ.
(Sama 11.1 Vṛ Pa 19)
ekamāsaṃ prathamāyāḥ pratimāyāh pālanena dvan māsau dvitīyāyāh pratimāyāh pālanena evamyāvadekādaśamāsānekādaśyāh pālanena panca sārdhāni varsānyarthatah pratipāditānīti.
(PrasāVṛ Pa 294)