(a) By October 30, 2006 no less than 50 percent of the buses in its fleet with which it provides fixed-route service are readily accessible to and usable by individuals with disabilities, including individuals who use wheelchairs.

(b) By October 29, 2012, 100 percent of the buses in its fleet with which it provides fixed-route service are readily accessible to and usable by individuals with disabilities, including individuals who use wheelchairs.

(c) Request for time extension. An operator may apply to the Secretary for a time extension of the fleet accessibility deadlines of this section. If he or she grants the request, the Secretary sets a specific date by which the operator must meet the fleet accessibility requirement. In determining whether to grant such a request, the Secretary considers the following factors:

(1) Whether the operator has purchased or leased, since October 30, 2000, enough new OTRBs to replace 50 percent of the OTRBs with which it provides fixed-route service by October 30, 2006 or 100 percent of such OTRBs by October 29, 2012;

(2) Whether the operator has purchased or leased, between October 28, 1998 and October 30, 2000, a number of new inaccessible OTRBs significantly exceeding the number of buses it would normally obtain in such a period;

(3) The compliance with all requirements of this part by the operator over the period between October 28, 1998 and the request for time extension.