You would have stayed UK resident if you were abroad less than a full tax year (6 April to 5 April the following year). This means you usually pay UK tax on foreign income for the entire time you were away.
Wages or other employment income brought back from abroad is not taxed when you return.
As you will not be working when you come back you will not need to register for Self Assessment.
Any earnings on your deposits will be under UK tax when you return because you will be a resident again.
That is correct. While you were not resident in the UK your wages were not taxable. Bringing them now into teh UK would not be taxable.
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