thanks for the heads up. I had been checking playstore and its version is older.
2) some people may have v 1.94 or v 2.01.
I just completed some more testing.
back on v 1.94.....go into app and cleanup before playstore update, do playstore update
-either through normal or recovery seems to make no difference as
does not change version in app.....Yes I know thats off topic
3) Do a full uninstall next
custom recovery install zip from sdcard from Athos links.
script appears to work.....you go back to menu to do reboot and you may see next image
I chose yes and then checked app version on reboot.
currently this is unresolved for me and yes I have checked I still have true root.
FYI and YMMV
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question for any one interested who has previously used chainfire's app.
after doing post one......go into Android
go into app drawer
go into supersu
go into settings
what version do you see?
If one user can reply to say they see 2.14 then the fault lies at my feet.....I shall move off Linux giggles
If one user can reply to say they see (say) v 1.94 then my method was correct and I may need to report bug upstream.
thanks for reading