Correct rate for class 2 NIC payment

My CF83 application was accepted a while ago and I have successfully made payments for gap years and years since my application was accepted. My pension forecast has been lower than I expected, given my back-payments, but I recently learnt that a period of being contracted out is the cause and also that my belief that I could pay for a maximum of 35 years was erroneous. So, getting to the point, I had confirmation that payments for an additional 2 years (plus upcoming years) will improve my pension to the maximum. If I've understood NIM72270 correctly then the rate I should use is the rate for 2022/2023, i.e. £3.15 / week. Can that be confirmed by someone on this forum? If I 'play safe' and use the 2023/2024 rate (£3.45/week), will any over-payment be applied to upcoming years? Thanks.

Hi,
Voluntary class 2 National Insurance contributions for the 2022-2023 tax year are £3.15 a week so £163.80 for the year.  
Payment of this amount should be received by 5 April 2025 or the amount required may be due at a revised higher rate.
If you would like to check your pension entitlement that you may wish to obtain a State Pension Forecast via Check your State Pension forecast
Thank you.