Question about annual income requirements for PR through HSP system

I'm posting this on a newly created alt to protect my privacy.

I'm currently on a 3-year engineer visa and have 75 points under the highly skilled points system. Given the new restrictions coming in after the 31st of March 2027 where only holders of a 5-year visa will be able to apply for PR, I have scrambled to negotiate with my employer for a salary increase that would put me past the 80 points required.

My question is, if I sign a contract tomorrow increasing my salary (for example) from 8 million yen to 9 million yen which would grant me the additional 5 points, would the timer start from 8th march 2026 allowing me to apply on the 8th of march 2027? Or would I, on the 8th of march, have to certify that I received a total of 9 million yen worth of salary and am projected to receive 9 million yen the next year? In essence, is having a salary contract enough to start the timer or will 9 million worth of paychecks have to hit my account before my application too?

Thanks.