The OP may wish to also refer to 6.14(c):
(c) Subsequent Occupants who are not Co-occupants and who commenced occupancy on or after January 1, 1996, where the last Original Occupant vacated on or after April 25, 2000. When all original occupant(s) no longer permanently reside in a rental unit, and the last of the original occupants vacated on or after April 25, 2000, the landlord may establish a new base rent of any subsequent occupant(s) who is not a co-occupant and who commenced occupancy of the unit on or after January 1, 1996 without regard to the limitations set forth in Section 37.3(a) of the Rent Ordinance unless the subsequent occupant proves that the landlord waived his or her right to increase the rent by:
(1) Affirmatively representing to the subsequent occupant that he/she may remain in possession of the unit at the same rental rate charged to the original occupant(s); or
(2) Failing, within 90 days of receipt of written notice that the last original occupant is going to vacate the rental unit or actual knowledge that the last original occupant no longer permanently resides at the unit, whichever is later, to serve written notice of a rent increase or a reservation of the right to increase the rent at a later date; or
(3) Receiving written notice from an original occupant of the subsequent occupant’s occupancy and thereafter accepting rent unless, within 90 days of said acceptance of rent, the landlord reserved the right to increase the rent at a later date.