They have low production capacity but so far they expended small part of their stock of cruice/balistic missiles. Also, they are flying low because they weren'

They have low production capacity but so far they expended small part of their stock of cruice/balistic missiles. Also, they are flying low because they weren't able to destroy Ukrainian air defense so flying high is still quite dangerous. When they're flying low air defence has no enough time to react - it's still dangerous but less so.