Civil Service Compensation Scheme Calculation

Fruitloop80

Good afternoon,

After being off work for a number of months with no sign of returning in the short/medium term, I have been dismissed on the grounds of capability. 

I was employed by the Civil Service for just over 21 years and as such will be receive a payment under the Civil Service Compensation Scheme. My understanding is that I am entitled to a maximum of 21 months salary (1 month for every year of service) however my union representative has worked this out to be significantly less due to my age (42). 

I cannot find anything to say that age is a factor in any calculation?

The only calculator I can find on the Gov website is annual salary x number of years service divided by 12. 

So my calculation is 37000 x 21/12 = 64800 but my union representative has worked it out to be around 43000. 

Does anyone have any knowledge or experience of how they calculate your payment?

Thanks in advance