Thinkpad Tablet 1838

[Legion99]

Good morning.
I was an unfortunate purchaser of a Lenovo ThinkPad Tablet, 1838 model running on the NVIDIA Tegra 2 T20 1.0GHz dual-core CPU.
Within 18 months of purchase, some years ago admittedly, we received an update to Android 4.03 then Lenovo pulled the pin on the tablet and ended all updates and support.
Apart from a wayward start button, a known fault with these and which I fixed, the tablet has been great and I have / had no reason to update.
But now, the old android system, 4.03, is preventing me from using certain apps and other newer apps are locking out due to 4.03. XDA sort of gave up soon after Lenovo and the only upgrade available is CM10 which in itself is getting old.
I then had the thought of putting a Linux distro onto the tablet. Despite a lot of time searching I have been unable to find any update / Linux rom for this tablet.
My question is does anyone know of an updated rom, Linux or otherwise, for the 1838 series.
This was, and still is a realy good table and honestly, I was very disappointed with Lenovo's treatment of buyers of this expensive tablet and if I do have to purchase a new tablet it will not be anything from Lenovo.

Any ideas would be gratefully received.