HELP! Bricked HTC One M8 (UK, Unbranded)

Help! I've bricked my HTC One M8!

I had TWRP and root and wanted to install the latest OTA update. I downloaded what I thought was the stock recovery and flashed through Fastboot.

Everything was fine, rebooted and the OTA updated downloaded and installed successfully. However, on re-starting, the phone is stuck on the HTC One logo screen. The power button is un-responsive.

I can power down with "power and up" and get to fastboot with "power and down". If I select "Recovery" I go to the stock recovery screen.

It's an unbranded UK model and I did a get var all before flashing:

(bootloader) version: 0.5
(bootloader) version-bootloader: 3.19.0.0000
(bootloader) version-baseband: 1.25.214500021.06G
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 4.16.401.10
(bootloader) version-misc: PVT SHIP S-ON
(bootloader) serialno: SH44PWM10125
(bootloader) imei: 358714054436740
(bootloader) imei2: Not Support
(bootloader) meid: 00000000000000
(bootloader) product: m8_ul
(bootloader) product: m8_ul
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B10000
(bootloader) cidnum: HTC__203
(bootloader) battery-status: good
(bootloader) battery-voltage: 0mV
(bootloader) partition-layout: Generic
(bootloader) security: on
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: 3aa067db
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0

This is the recovery that I downloaded and flashed:

recovery_4.16.401.10.img

Any idea if I can revive this thing?

Thanks all!