Latch power on-off circuit
As you currently have it, it's very likely that E in the off state is high, but that depends on what "LOAD" is. If LOAD somehow disconnects or is extremely high impedance, then you have no idea where E is.

Instead, I would tie a very large ~1Mohm resistor across the load to ensure that current can get around the load even in the "off" state. This will ensure that E is set to high even in the off state. It won't consume any current in this state because there's no direct path to ground until MCU Power Off is pulled.