Mandate Haifa postmarks / Saturday mail: 10 AP 1930 stampless "certified official" cover on OHMS stationary from "Station Office 'B' Division Haifa" (cachet on front) to Arab prisoner at Acre Prison, tied by HAIFA BAZAAR.B.O. postmark GD-108 on 1st day of use and backstamped same day HAIFA transit; dispatched unusually on Saturday 12/04 (this possible per postal regulations at post offices & postal agencies in Moslem areas, where their day off would be on Fridays) & backstamped same day ACRE arrival using Dorf-3 + trilingual Prison cachet. As prisoner have left (released), re-routed to MAJDAL where arrived next day (pmk Dorf-4). Cut open at back, sliver missing; estimated value $100+