I may be incorrect on this. Shawn has a thread under the JField forum on Base Guard. If you update the LS and not the receiver, then your system may not work properly. I am going to delete my previous post so it's not misleading or confusing.
Last night I tested the system after updating the LS and T2 (older board).
Initially the LS did not receive corrections. I tapped (to base) on the base connect page, started the base and it worked.
I've noticed that after updating, the system will display unusual behavior. I have an algorithm I follow when the base doesn't connect. Resending the base setup is near the bottom of my process when I can't connect. Last night I did this early in the process and it resolved the problem.