ADC12DJ5200RF: How does the DUAL DES Mode work?

Part Number: ADC12DJ5200RF

According to the datasheet of ADC12DJ5200RF, it has three Functional Modes:

In my opinion, DES Mode means:

But how does the DUAL DES Mode work?The datasheet says "Dual-input single-channel mode is equivalent to dual channel mode, except ADC B samples out-of-phase with ADC A (single-channel mode sample timing)", and the  Register Field Descriptions says "ADC channel A samples INA± and ADC channel B samples INB±".

For this,I have some questions about DUAL DES Mode:

Q1. "ADC channel A samples INA± and ADC channel B samples INB±" means      channel A only samples INA± and channel B only samples INB±      or      channel A samples INA± and INB±, channel B also samples INA± and INB±?

Q2. "except ADC B samples out-of-phase with ADC A", how to understand "out-of-phase"? It means      ADC A samples on the rising edge of the clock, and ADC B samples on the falling edge of the clocks      or        the phase of the analog signal sampled by ADC A is opposite to that of the analog signal sampled by ADC B?

Q3. In DUAL DES Mode, do the analog signals input by INA and INB need to be correlated? If so, what kind of association is needed?

Q4. Could you please give an example to explain the use of this mode in detail?

Q5. Could you please give a figure like Figure 2.DES Mode sampling to explain how does the DUAL DES Mode sample?