how to safely upgrade r0 hikvision cams fw from 5.1.6 to 5.4.5?

[discoduck]

Hello, i have few hikvision r0 cams (2X DS-2CD2032-I and one DS-2CD2732F-IS), bought about 7 years ago from china, they had some multilanguage fw on it including english, firmware 5.0.2, the serial number included CCRR code (if i remember correctly it's some kind of russian region).
Anyway i want to upgrade them to latest firmware, so using the tftp method i upgraded to 5.1.6 firmare, based on this post that referenced he had same code in the firmware and reported success:

DS-2CD2332-I Firmware 4.0.9 with "CCRR" in serial number. Recommended firmware?

I have an old DS-2CD2332-I that comes with 4.0.9 firmware and has "CCRR" in the serial number. The camera is dated some time in 2013. I would like to upgrade to a newer firmware version like 5.1.6 or 5.2.5. I wonder if I can upgrade it via the web UI or I should use TFTP. And is this a Chinese...

ipcamtalk.com

My upgrade went fine, language is still full enlgish, but the poster above reported that his firmware changed from CCRR to CCWR which means he can upgrade using any type of international firmware, if i understand correctly.
I followed the same procedure but my code changed from CCRR to CCCH, so what do you think it's the best way to proceed if i want to upgrade to 5.4.5, the last fw?
Now that i have CCCH im afraid that any fw upgrade it's going to brick or change the language to chinese, and i also read that these new firmwares have a downgrade block.

Thanks in advance for any advice

 

[wittaj]

If the cameras are working as intended and meet your purposes, there is no need to upgrade. Many times an upgrade breaks or introduces something that then impacts the camera that was working.

 

[alastairstevenson]

R0 firmware of 5.4.0 or earlier has the Hikvision backdoor vulnerability.
The 5.4.5 or 5.4.41 versions are stable and fix quite a few problems.

Any cameras with CCCH in the serial number are Chinese and will stop working when updated with stock EN/ML firmware of 5.3.0 or higher.
This can be applied if the cameras are converted to English using the brickfixv2 method as per the link in the signature below.

 

[discoduck]

thanks alastairstevenson, im going to give it a try tomorrow considering it looks a bit complicated, i also need to figure out whether i dont have to follow some of the steps considering my cams arent bricked.
EDIT: going through the thread in your signature i see many were already in my position and successfully updated.

Im going to start with the one i already updated to 5.1.6 from 5.0.2. I just wonder why in my case the serial, after this upgrade, went from CCRR to CCCH while for the other poster in the thread i quoted it went from CCRR to CCWR. Because if i can do the same for my other two cams the upgrade for them it's going to be a lot easier.