19.6.4 Time Delays During Wake-up
The delay between a WDT time-out and the beginning of code execution depends on the Power-Saving mode.
There is a time delay between the WDT event in the Standby Sleep mode and the beginning of code execution. The duration of this delay consists of the start-up time for the oscillator in use and the PWRT delay, if it is enabled. Unlike a wake-up from the Standby Sleep mode, there are no time delays associated with wake-up from the Idle mode. The system clock is running during the Idle mode; therefore, no start-up delays are required at wake-up.