Looking in the logs there are issues with bad flash memory, so it is possible this won't be able to be done and a replacement device will be required.
[ 4.077675] yaffs: block 56 is bad
[ 4.082837] yaffs: block 166 is bad
[ 4.105557] yaffs: block 647 is bad
[ 4.140802] yaffs: block 1394 is bad
[ 4.165753] yaffs: block 1921 is bad
[ 4.192177] yaffs: block 2486 is bad
[ 4.278521] yaffs: block 4342 is bad
[ 4.354714] yaffs: block 5965 is bad
[ 4.356187] yaffs: block 5997 is bad
[ 4.368367] yaffs: block 6257 is bad
[ 4.398699] yaffs: block 6910 is bad
[ 4.414631] yaffs: block 7253 is bad
Instead of the old software it is running (which appears to only be a beta release candidate, tc-7.3.7-rc2-0-g01c84fd), you could try to upgrade it to a more recent release such as TC7.3.21 via the web interface. This may work depending on the flash it is written to. I'd suggest upgrading it twice if the first update works to get both images stored on the device to a recent version. This may give you a little more life out of it, but, as you mentioned, it has been an end of support device for two years already, so a newer, supportable model would be recommended.
Wayne
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