The ornamental design for an adjustable bedframe, as shown and described.
FIG. 1 is a front and right side perspective view of an adjustable bed
frame showing my new design; and
FIG. 2 is a view similar to FIG. 1 showing the frame in an upright
position.
For convenience of illustration, the slightly bent reinforcement of the
frame, shown in FIG. 1 below the slats at the front of the middle portion
thereof, is omitted in FIG. 2.