April bonus and tax code change query

Hi there, I earn approx. £34,500 base salary and will receive a bonus this April of approx. £1500. I've seen my payslip and my tax is almost double this month. Obviously my monthly pay will reduce back down to what it is meant to be from May onwards. On these forums I've seen conflicting information about how my overpaid tax will be repaid to me. I've seen some agents saying that I should receive the difference in tax back in my May pay packet, others say I will pay less tax across all of the remainder of the tax year spread across the 11 months and one of them had said you will need to apply for a tax rebate after May. So how will I receive the overpaid tax back? As a secondary question, my tax code prior to this first tax month of the year was 1187L and now it shows on my most recent payslip as 1086L. Can someone explain the changes to me please as nothing has changed that I'm aware of so don't understand why my tax code has changed or what the change in number means for me in real terms? Thanks, Craig.

Hi,
While tax overpaid due to a one-off bonus would usually be refunded over the next few months of the tax year, the doubling of your tax liability and the reduction in your code could be the result of something else.
Please contact us by webchat or phone via:
Income Tax: general enquiries, where we can review your code and record.
Thank you.