What was found
DURING TAXI OUT C HYD DEM PUMP PRESSURE WHEN FLAPS ARE IN TRANSITION , ACFT RETURNED TO GATE (BTB) AND MTX GROUNDED ACFT . DEFERRED ADP MTX TRANSFERRED TO DI# 69856 IAW MEL 29-11-3, MBCB 01/27/26, PULLED AND COLLARED C/B, MX PROCEDURES C/W, PLACARD INSTALLED, AND RETUENED ACFT TO SERVICE.