Th eonly other thing one cna suggest is to contact Tesco support - they certainly did have a reputation for being helpful.
Failing that one of the enthusiast sites may have people who can help:
https://forum.xda-developers.com/t/hudl2
One wonders whether Cyanogenmod, LineageOS or RemixOS are possibilities
Stop press - this may be worth following up:
http://www.markwilson.co.uk/blog/2015/07/complete-hudl-wipe-with-reflash-to-revert-to-factory-settings.htm
Acp
August 2017
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