My fault,
I added some pause commands for trying to test at my end & again forgot to remove them.
This attached version might work.
That's working perfectly now!
Phew!
It's really difficult to debug when I can't actually test it myself.
Otherwise I would have noticed that problem.
As you are using the Netgear firmware, have you left in the logging in from Login1.TXT & Login2.TXT?
In other words, has it worked without needing to visit the Telnet enabling URL, or have you perhaps not rebooted the router since you last enabled Telnet access via the URL?
The data you obtained manually was obviously not much to work with, but so far, it seems to graph O.K.
The attached is the graph set from your manually obtained data.
It shows a connection of around 16 hours.
Does that seem about right?