Right,... i understand now, thank you.
That vertical display got me wondering. We didn't experience those kind of problems yet, we only get a lot of CPDS FAIL in flight report display and other usual "windows" kind of errors, like att. trim caution at random.
One more question while we are at it. We have some airspeed discrepancy. Back up airspeed indicator is showing the same values as CPLT's readings however, PLT's reading is 5 to 10 kts lower than other two (10 kts at speeds lower than 50 kts).
At what point will the discrepancy become evident (arrow marking) on PFD due to SYS I and SYS II indication differences?