I suppose they do, but what they do are global changes and mods. While doing this, it imposes many minor problems, and if to consider that there are thousands of users, some part of users faces with minor issues... Support starts to fix the issue and when finishes it, that moment another upgrade/update on the server is being made, and everything starts over and over... So I think this procedure seems to be never ending nightmare if the main target of free hosting is being "The most up to date" rather than to be "the most stable".
My post regarding
"Are Upgrades of Servers worth of it?" you may read here.
About tickets - what I see from free hosting users posts is that either support tickets almost never answered, or the queue of tickets come to end only 2 weeks later...In my case I have an open ticket, which is already non-actual issue for me now, but it is still left open for 10 days.