I've seen STM active again in the evenings. As I've mostly been away from home I haven't really tested when it is working and when it isn't. I'm not sure if my area counts as congested or not. Certainly my TBB chart looks a lot better than it did but a lot worse than many I've seem...

This was my September SamKnows downstream report. Considering these are averages across the whole day I'd say it's hardly brilliant...
46.97Mbps Average
17.83Mbps Min 8pm, Sun 22nd Sep
63.74Mbps Max 6am, Sat 14th Sep