For the broken cycles, it’s difficult to pinpoint an exact cause, but as @timd1971 mentioned, the environment you’re working in could have an impact on your data collection. For instance, an electrical solar power plant might generate electromagnetic interference that could affect GNSS receivers.
Regarding the Local Easting and Northing coordinates, we recommend creating a new project in Emlid Flow 360 and importing your collected data. This will allow you to switch from a global coordinate system to a local one. We also have a Support Tip on our Community Forum that explains this process in more detail.