Since I logged in this evening, I've noticed that I get a strange flickering when I'm riding my horse. It seems to be much worse when I'm in areas where I get low fps, especially when I get below 15fps. When I'm not moving on the horse or not on the horse at all I don't get this issue. I haven't had it before today, 13/4/17. Relogging after /lotime doesn't have any effect. The new update seems to be causing this issue, because as far as I know nothing else has changed on my computer.
EDIT:
I now seem to be getting some minor flickering while I'm not on the horse but walking around.