"A veteran is someone who has served in the armed forces for at least one day. There are around 2.6 million veterans in the UK. When servicemen and women leave the armed forces, their healthcare is the responsibility of the NHS." (the same as any other citizen/resident of the UK...)
https://www.nhs.uk/NHSEngland/Milita.../veterans.aspx

On the flip-side...
https://thewaltercumpershunterclub.wordpress.com