Among another  things, GRU officers have been found to leave besides   many digital footprints, in peculiar  erstwhile   utilizing mobile phones, including for viewing delicate  pages linked to Russian intelligence. So they started utilizing land phones again. It is worth reminding that the scope  of expulsions of GRU officers from Europe made it hard  to organize operations and control agents abroad – which was 1  of the reasons for the failure of the invasion of Ukraine.