For the first time that I can remember, it's not syncing well between my laptop and phone. This is since installing the 10.11.4 and 9.3 public betas.
The phone seems fine but the laptop, even if that's where I send the messages from, doesn't update the "read" status sometimes nor get the reply for a few minutes, despite the phone getting it immediately. I logged out and back in again to see if it fixed the issue; it was slow to log back in but I had no issues doing so.