I think they will still be able to cope with their studies and some local volunteering 1 weekend per month
"Community volunteering: The vast majority of ****agers would take this pathway.
It would require them to spend one weekend a month volunteering, for one year - 25 days in total.
The voluntary placements would be in the local community, with organisations such as the police, the fire service, the NHS, or charities that work with older isolated people."
This is not national conscription. If they want to, they can apply to join the armed forces for a year.
"Military training: 30,000 ****agers would be able to take up places to spend a year full-time in the armed forces.
Young adults would need to apply for the programme and tests would be used to select the best candidates."
https://news.sky.com/story/national-...tions-13143820