I'm all for Ukraine winning the war defending their borders but I totally get it. You have only one life, but there are over 190 countries. Not everyone is so attached to a specific country, I know I'm not. Even if you're winning, there are still so many humans dying. People are spending life savings for bogus medical treatment to avoid dying prematurely, why would we not expect people spending life savings to avoid dying prematurely in a war?
Also the war is brutal and a lot of the casualties from Ukraine are generally self censored. Conscripts are mostly put in with territorial defense forces which get the shitty gear and little training and they are mainly used to hold the front line and generally don't have many options if they Russians decide to attack their fortifications.
Maybe ukies should consider alternative service for pacifists etc. Maybe as ambulance corps, civil defence, munitions factory workers, mining, farming, anything that supports the war effort. After giving such option and they still shirk, then take legal action.
It says that they are sent to Britain to be trained. Unless they're being flown in to some military complex directly, why wouldn't they just run away once they've cleared immigration in the UK? Would British police arrest them even if they haven't broken any laws in the UK? Do Ukrainian army personnel have authorization to capture them and arrest them even on British soil?
I don't have any information but I'm willing to bet those are volunteers, not conscripts. If they are conscripts, they probably volunteered to be part of those units.