Basic PAYE Help

I'm going totally round in circles and just not sure what I am doing wrong. Based in UK. Tax code for 2023/24 is 1159L. Monthly gross salary from April 2023 to December 2023 is £4033.33 (£48400 / year). Auto enrollment pension contribution = 6% Pay increase from January 2024 (to March 2024) to £55000 / year. So monthly = 4583.33 Questions: - by my calculations that equals £50049.96 annual gross salary for 2023/24 (36299.97 + 13749.99) Therefore, to stay under the 40% tax group, can I carry on paying 6% pension contribution or does it need to increase? I keep working it out that I need to increase i but just can't work out the logic! From April, 2024, I need to increase contribution to something like 13% to stay in the 20% bracket? To add to the mix, I may get a £5000 bonus in January too! Any help much appreciated

Hi TheRunner1989,
The threshold to pay tax at 40% is £50,270 if not in Scotland.
If this is the case for yourself then based on your annul salary £50,049 you will still be in the basic rate 20% band.
Thank you.