It seems that my phone log doesn't sync anymore. Even though contacts and messages are in sync, log is stuck and shows latest entry in Feb. Could that be because I updated phone's firmware sometimes in Feb too?
We've identified the problem (yes, it's related to phone reset during firmware update), fix will be included into one of the future versions. As a temporary solution I can propose to clear all existing logs in the web interface, new logs should sync without problems after that.