Accounting dates

Dear John,

It seems I have trouble to understand how the dates work…
Example from BPP practice question bank.

44, Gamma co prepares its financial statements for the year to 30 September each year. The company pays the rent for its premises quarterly in advance on 1 February, 1 May, 1 August, 1 November each year. The annual rent was 120 000 per year until 30 April 20×8. It was increased from that date to 144 000per year.
What balances were included in the statement of profit or loss and the statement of financial position for the year ended 30 September 20×8?
I started to calculate:
120000x 4/12 (since the rent went up at the end of April and it is quarterly paid, the next payment was due at 1st of May)
+144000 x 8/12

BUT
In the solution:
120000 x7/12 + 144 000x 5/12

Could you please help me to understand why?

Thank you!

Kind regards,
Katalin