Change in tax band during financial year, which personal allowance

A simple question but didnt find it explicitly answered online. If during a financial year my income goes up that means I move into a different (higher) tax band. What does that mean for my personal allowance (savings/dividend/...). Which allowance figure do I use, the one before the increase in tax band, the one after the increase, some combination of the two?

Hi htop123,
It will be based on what your final total is at the end of the year to ascertai nhow much savings allowance you are due.
If you are a higher rate taxpayer it will be the £500 There will be no change to personal allowances unless your income exceeds £100,000.
Thank you.