Leaving the building at 8:50 with a 40 minute drive puts you on area at 9:30, which gives you 1 hour to deliver 16 air stops. You are also a cover driver which means you may not be that familiar with the area. You took quite the gamble trying to deliver ground rather than delivering straight air.
You asked what could happen if you have late air? Well, they will print your delivery records to see if you delivered any ground. If you did you will be given a warning letter for failure to follow the methods. The gamble is not worth it----run straight air if you have to.