Sounds like it is an approximately 9.5-bit ADC now, instead of 9-bit like the RP2040 was. So... not much change.
Datasheet section 12.4.1 "Changes from RP2040"
- Removed spikes in differential nonlinearity at codes 0x200, 0x600, 0xa00 and 0xe00, as documented by erratum RP2040-E11, improving the ADC’s precision by around 0.5 ENOB.
- Increased the number of external ADC input channels from 4 to 8 channels, in the QFN-80 package only.
