I want to replace the Bolt image by a generic one as it doesn't seem to be possible to disable the auto update check in this image and I tend to press the wrong button on startup 
Now I noticed there are two images which do not seem to be branded:
Huawei_E5372_Firmware_21.270.13.00.00_Universal.dg tk
Huawei_E5372_Firmware_21.290.21.00.00_general.dgtk s.html
On the general image it says it's not possible to go back to an older image after flashing.
Can someone explain what the difference is between these two images and which one would be the best option for me? I'm using it in different countries so in general not having a branded one is a plus.
thanks
sugus

Now I noticed there are two images which do not seem to be branded:
Huawei_E5372_Firmware_21.270.13.00.00_Universal.dg tk
Huawei_E5372_Firmware_21.290.21.00.00_general.dgtk s.html
On the general image it says it's not possible to go back to an older image after flashing.
Can someone explain what the difference is between these two images and which one would be the best option for me? I'm using it in different countries so in general not having a branded one is a plus.
thanks
sugus