Does scope DC gain accuracy increase with Hi Res mode?

[fonograph]

I saw in datasheet of scopes from Keysight,Lecroy and R&S  specification called DC accuracy,its usualy between 2% to 0.5%.8 bit scopes are around 2%,10bit 1% and 12bit 0.5%,I mean the real hardware resolution of the ADC.

If I understand it correctly this spec tells how good is the scope at measuring voltage amplitude of signal,kind of like multimeter.This spec can be limited by either noise,non-linearity or resolution.

 My question is,can so called hi res mode,HD mode or eres increase the DC  accuracy? I know that oversampling the ADC can decrease the noise,increase the resolution but does nothing to inherent non-linearity of ADC.Can these oversampling hi res modes help?

I like the Lecroy hdo4000 becose it have 0.5% accuracy,I wonder if R&S RTO can match its DC accuracy,its only 8 bit 2% but it have 10 Gs/s ADC instead of 2.5 of lecroy so it can oversample 4x,will that increase the DC accuracy? What about Keysight S,can hi res mode increase the DC accuracy?