Pulling the battery sets the B, T, F to 1, 0, 0, which is effectively stock. To put it in actual 'Stock mode' you do need an SPS.
FWIW, I've had Revo 1 and 2+ on my ED30 (same engine as ED35, albeit yours is a CDL and ED30 is BYD, but same ECU) and when pulling the battery, it ran stock boost in the logs (1.2 bar spike, 1 bar held). Enabling 'Stock mode' made zero difference.
The ECU software basically has 3 levels. Level 1 is the base operating system, Level 2 is the core functions and Level 3 is the tuning. Level 3 is what the tuners alter. It stays resident permanently until reflashed back to stock by a dealer, or flashed with a different tune.