Tortilla

I have two jobs: 1. Part-time, low salary, contribute to a local authority pension scheme (LGPS). 2. Part-time, larger salary, pension situation that is non-LGPS. This gives total gross annual salary of c.£15k, split between the two jobs. I want to buy more pension years via job 1. LGPS scheme. I’m trying to work out the maximum additional amount I could pay per year and still receive full tax relief. Via job 1. (LGPS) tax relief would relate to the maximum of my salary and could be sorted via payroll. But - I understand the HMRC rule allows for tax relief on total annual income (up to 60k). So: If I made a lump sum of my total annual salary (both jobs; c. £15k), direct to my LGPS pension scheme rather than via payroll, could I apply to HMRC for the full amount of 20% tax relief on that? Many thanks in advance for your thoughts.