For the past week or so, folders have been available in many Metro buses summarizing, in very brief form, service changes that were to go into effect over the weekend on 19 routes and 43 route variations, such as branches and express services.

Some changes were significant: the cutback of the two major branches of the No. 4, Arlington Boulevard/Pershing Drive line in Virginia, from a 30-minute to a 40-minute midday frequency. Service was curtailed also on the busy No. 3, Lee Highway line. Trips are being dropped as of today on the No. 66X, which runs between Rosslyn and the future West Falls Church subway station, because it failed to attract the hoped-for number of passengers.

Changes in the District were minimal: improved after-school service on two lines, the short extension of another. Several schedules in Maryland were changed, including those on the T line serving Bowie-Bel Air.

"Check new timetable for the exact schedule," was the advice offered in the folder.

One Arlingtonian asked for a new schedule from the Rosslyn subway station attendant on Friday. None were available, the attendant said. He asked again yesterday. A different attendant, then on duty, pointed to three cardboard boxes filled with timetables, then shrugged.

"When I learned two weeks ago that the schedules were being changed, I ordered a supply" from Metro headquarters, he said. "And look what I got: 4,000 of the old schedules," and not a single new one.