737 CL Derate confusion
Please help... i am flying a 734 with 23.5k engines. Recently, my company told me that the engines have been derated to 22k. And that if required, i can simply disconnect the auto throttle and manually set, via the relevant tables, the 23.5k N1 setting. The options are not available to me on the FMS, only 22k is available. I am confused because i understood that it was a maintenece procedure? I will appreciate any explanations asap, cause we flying heavy loads that require the 23.5k thrust to get airborne. Thx...