Income tax re-adjustmed over the year?

Hi all

This is my first post so I am hope I have put this in the right place.

I have a question regarding income tax -

I recently started a new job in June, but my employers HR department took some time in setting up my pay, so long story short I got 2.5 months worth of pay lumped into one paycheck, which for just that month took me into the 40% tax band.

Will my income tax re adjust itself in the following month or will I have to wait till the end of the tax year to claim it back as I am unlikely to go into the 40% band over the full year.

thanks for your help in advance

Jordan