[Ma8ee]

Maybe they couldn’t and just sent the SMS to a lot of random numbers. Those that belonged to mothers at the frontline naturally tried to call their sons.

[rezeroed]

Right. Still curious about monitoring cell activity only during calls. Thinking if you can monitor the cells, just look at the front line cells for comms.

[jinglebells]

They didn't know where the front line was?

[rezeroed]

You're involved in a conflict and you don't know where the front line is?

[TeMPOraL]

They knew where the front line was, they were trying to learn where the Ukrainian forces were positioned along that front line.

[rezeroed]

Right, so back to the question - why not just monitor front line cells for activity, which i think can be done without making calls?

[TeMPOraL]

I'm guessing: they needed a way to distinguish the troops from the civilians living in the area. By triggering a mass amount of calls to frontline soldiers, they made their positions light up in front of the overall background.