Second pic.

Third pic.

You should be watering once a week for an hour or as long as it takes your sprinkler system to fill a cat food can (inch of water). You can't go cold turkey from your current watering to the correct watering. The grass roots are not deep enough to last a full week right now. You have to wean yourself off this 2x weekly stuff. By the time you get it weaned it will be time to go to once every 2 or 3 or even 4 weeks.

You should be mowing at the mower's highest setting to favor the St Augustine. If you mow it high it will wipe out that bermuda in the hell strip.

Have you fertilized in the past year? If so what did you use and when?

I use the seasonal Scott's fertilizer - the general ones sold at Lowe's. I currently mow it pretty high, will have to check the settings on my mower.

Is Bermuda, the vine-like creeping grass?

Bermuda is fine bladed grass.

10 minutes is nowhere enough to keep st augustine happy.

To achieve 1 inch is 600 gallons per 1000 sqft.

For the strip area, the best way to water it is soaker hose. In the past, I'd lay it out on the strip area right in the middle and barely turn it on for the night. Repeat every 2 weeks. Worked pretty good.