WF-3720 - firmware version doesn't changes after downgrade

[WF-3720 - firmware version doesn't changes after downgrade]

By following this recommendation, will I need to buy an Activation key?  I really didn't want to go "chipless", just downgrade the firmware to allow 3rd party print cartridges.

What firmware version is FWF469TL.efu

 

[WF-3720 - firmware version doesn't changes after downgrade]

Epson firmware update over the Internet today to 30.74.CL27J9 caused the printer to stop recognizing the installed 3rd party cartridges.

Downloaded WIC, bought a firmware key, put the printer in maintenance more, ran the update ( CL26H9) which said it transferred OK to the printer.

The printer seemed to run the firmware update but when it seemed to complete it displayed a screen that said it still has the 30.74.CL27J9

 

 

Powered on/off a couple of times, but no change, firmware is still 30.74.CL27J9 and ink cartridges are not recognized.

 

Tried to re-run the process but WIC says it's already done it.

 

How can I fix this?

 

Thanks.