First, let's calculate the distance between City A and City B based on Amy's travel.
Amy drove for 4 hours at a speed of 80 km/hr. The distance (D) she covered can be calculated using the formula:
\[ D = \text{speed} \times \text{time} \]
Substituting in the values:
\[ D = 80 , \text{km/hr} \times 4 , \text{hours} = 320 , \text{km} \]
Now, we know the distance from City A to City B is 320 km.
Next, we determine Ally's speed. Ally drove at 1.2 times Amy's speed:
\[ \text{Ally's speed} = 1.2 \times 80 , \text{km/hr} = 96 , \text{km/hr} \]
Now we can calculate the time it takes for Ally to travel the same distance of 320 km using the formula:
\[ \text{time} = \frac{\text{distance}}{\text{speed}} \]
Substituting in the values for Ally:
\[ \text{time} = \frac{320 , \text{km}}{96 , \text{km/hr}} \approx 3.33 , \text{hours} \]
This time can also be expressed in hours and minutes. Since \(0.33\) hours is approximately \(20\) minutes (since \(0.33 \times 60 \approx 20\)), we find that:
\[ \text{time} \approx 3 , \text{hours} , 20 , \text{minutes} \]
Now, Ally left City A at 6 am. Adding the travel time to her departure time:
\[ 6:00 , \text{am} + 3 , \text{hours} , 20 , \text{minutes} = 9:20 , \text{am} \]
Thus, the time Ally arrived in City B is:
\[ \boxed{9:20 , \text{am}} \]