wrote: The test date is only on the shipping box, however, you could also use the date code which is on the unit itself before the MAC ID. Anything on or after the date codes below for each model includes the new bootloader from the factory:
ER-X - 1818G
ER-X-SFP - 1820G
EP-R6 - 1830G
Based what is said above
ER-X code of 1821G with a Test Date of 05/28/18
sudo md5sum /dev/mtdblock2
828a6788a539809103bd42d121634211 /dev/mtdblock2
That md5 shoud be the new bootloader....