I've moved to the UK in September 2022 therefore became tax resident of 22/23 year. I was working for employer based in Ukraine where salary is paid in two payments for one month, so salary for August was firstly paid in August (before I moved to the UK) and final payment was made in September when I was already in the UK. As I understand I can split tax year and pay UK tax on foreign income based on the time I were living in the UK.
The question is should I add August salary while calculating total pay from for 22/23 year? If so should I add 100% of that salary or only part of it proportional to the amount of payment made in September?