The Essentia Level Emitter does not update blocks that are not directly adjactent to it. That is, while it starts/ceases charing a block, any redstone wires, repeaters, etc. that are attached to it does not change accordingly.
The problem is found with AE2 rv3 beta6, Thaumcraft 4.2.3.5, forge 10.13.4.1614 and Thaumic Energistics 1.1.3.0. And it can be reproduced with a brand new superflat world with just these above mods installed(besides Baubles, of course).
Procedure:

1. Set up a ME network that contains:
   A power source (essentia vibration chamber)
   A ME chest with a essentia cell
   A warded jar with a essentia import bus attached
   A essentia provider attached to an automated alchemy device
   Some essentia level emitters , each pointing to a stone block with a redstone on top and
   Some cables to tether them together.

The essentia level emitters are set to emit signal when the Metallum level is above 10. Put some iron nuggets inside the automated alchemy device.

2. Add two phials of Metallum essentia to the jar. While the essentia enters the network, these emitters are activated. However the redstones are not charged.
   

3. Manually break these redstone and replace them. They are now properly charged.
   

4. Start the duplication of iron nuggets. As the essentia is drained, these emitters stops emiting signal. However the redstones are still charged.
   

Please consider about this problem. Thaumic Energistics is a great mod for automatizing thaumic process, but this problem renders my essentia managing system rather unconvenient. Thx.