We'll be there the same time as you! Been at CSR for Labor Day week for the past few years.
Maya Grill is usually not a problem, but we've found if we make a res the day before or in the morning we want to eat dinner there we can bypass the sometimes long standby line and get seated right away. The line can be long if the weather is bad and people just opt to eat at their resort and have a TS credit to use.
That time of year our dining ADRs get changed a lot, very weather dependent. We turn on the TV weather every morning while getting dressed. If it looks like a bad storm in the evening instead of just the usual quick downpour we'll make a res at Maya Grill and plan to leave the parks a little earlier.