I regret that we cannot confirm if split year treatment applies to your situation.
This is something you will need to work out for yourself.
You will need to apply the residence tests to your situation, to work out if your are resident.
You can them work out if split year treatment applies.
If it does, you will need to claim the split year treatment on a Self Assessment Tax return.
The tests can be found here:
RDR3 Statutory Residence Test
You can register for Self Assessment here:
Register for Self Assessment