Had a bit of a re-layout on the board today, pending the return of the newly CE compliant Diago PSUs. Was slightly surprised when the Wampler Ego lit up. I'm not electronics genius, but even I twigged that 4 weeks would be a hell of a long time for a pedal to retain residual charge in a capacitor somewhere.
Screwdriver out, back off, and I discovered it left Wampler with a Wampler branded battery pre-installed. Who knew? Not me until today.
So if you have a Wampler pedal and you're ignorant like me, it might be worth checking out. Mine would still have been loaded right up to the point it corroded ...