There is.
1. Unlock the bootloader by following
instructionsSony. (With the loss of DRM and all the attendant).
2. Throw on the internal storage
SuperSU.
3. Install ADB Fastboot + Sony drivers.
4. Download the phone in fastboot mode. (Turn off. Hold and hold the Volume Up + connect the cable. Hold until the blue diode lights up. The screen will be black, everything is OK. It is possible that the PC will install the driver.)
5. Stitch through the fastboot custom kernel, for example
Zombie.
fastboot flash boot boot.img
6. Boot into custom recovery, for example
TWRP.
fastboot boot recovery.img
7. From the recovery firmware SuperSU.