Thank you for your response and explanation–and the examples.
I had read that about people “topping off” causing issues with the charcoal canister. I am really hoping that it is a blockage or something similar as opposed to the charcoal canister (not a cheap fix–as I am sure you are aware). If the charcoal has been saturated does it ever dry out (or whatever)?
Do you have any idea if there is any explanation as to what would cause it to be working fine and then suddenly start the pump kicking off–literally the same day?