Received a following email from TP-Link.
Followed instruction, and used version 4 firmware.
Upgrade went well...did a factory restart after
Modem still shows:
Firmware Version : 3.0.2 Build 090522 Rel.24389
I guess, sharing the same firmware means, the version 4 model is using firmware made for version 3 !
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Thank you very much for your email requesting information about our product.
You can download the firmware version for V4. They share the same firmware.
»
www.tp-link.com/en/support/downl···V4#tbl_jIf you need any further help, please feel free to let me know.
To get technical support more quickly, please go to »
www.tp-link.com/support/faq.asp----------------------------------------------------------------
Yes, V3 and V4 share the same firmware.
Please follow the instructions to upgrade the firmware to make sure you can operate it properly.
»
www.tp-link.com/en/article/?id=107If you need any further help please feel free to contact me.