If you have been in China for 183 days or more then you are considered to be a resident tax payer and have to remit income taxes. That’s not continuous residence by the way, just total days within one tax year.
If you have been here less than 5 years then you only pay on your China sourced income.
I have no idea about UK tax law.
It sounds almost like you are going home now that you aren’t working here; if that’s the case then that may impact your decision.