Tc55 bootloader locked

Hello everyone, as Zebra/Motorola are not planning to release any further OS updates for the TC55 model above 4.4.3 android, and the bootloader is locked (cannot flash any other OS if not signed by manufacturer) I wonder what are we supposed to do with them? Is there any way of asking the manufacturer for a Unlock method for bootloader? Me as many others who bought this device will soon have to throw them away due to no OS update as all the apps will require at least Android 6 to run on.. maybe someone from Zebra could shed some light into this? Would be much appreciated!