business property corporate tax

Solo Ltd lets out a warehouse which is surplus to requirements. The building was empty from
1 April to 31 July 2020, but was let from 1 August 2020 onwards. The following income and
expenditure was received or incurred during the year ended 31 March 20

Date received/paid
£
1 April 2020 Insurance for the year ended 31 March 2021 (920)
1 August 2020 Rent for the six months ended 31 January 2021 7,800
1 August 2020 Security deposit equal to two months’ rent 2,600
1 March 2021 Rent for the six months ended 31 July 2021 7,800

ANSWER TO THE ABOVE QUESTION
£
Rent receivable £(7,800 + (7,800 ? 2/6)) 10,400
Security deposit 0
Less Insurance (920)
Property business income 9,480

DOUBT –

In the answer they have adjusted the rent receivable for 8 months but they have taken the insurance for the whole year why haven’t they apportioned the insurance for 8 months??