even though we haven't been getting scorching temps, fescue is a cool season grass, once it gets above 75, it starts to get mildly dormant.

and I think you are starting to see the signs of the warming up of the soil and dormancy of the fescue beginning.
946 is correct with raising the mower height. and you should only need to fert once or twice in the spring, the bulk of the fert for our areas is 2-3 in the fall...

depends on how often you want to cut grass.

I would also ask your mowers to rotate their pattern by 90* every now and again...

Could be too much fertilizer. That leads to a build up of salts in the soil, which draws the water away from the grass roots. So even though it is raining, your grass is acting like there is a drought. Especially since you see the yellowing in stripes where the fertilizer would have overlapped in your application (or been moved into rows by the mower.

Lay off the fertilizer for the rest of the year and have them mow high: 2.5 to 3 inches. That will give the blade more surface area to photosynthesize and so become healthier. This will give the roots more food and let them become more dense and so your brown bare spots will fill in too. It will suppress weeds naturally, both by creating a more dense lawn and by shading the ground preventing germination of weeds.

How much water is it getting per week? What kind of grass is it?

Heat no rain

Grubs?

honestly it looks fine to me.

https://ibb.co/zNGq9jH

Left to right - April to June

Back in March/April I dropped some milorganite and it was fantastic. In May, I hired a new landscaping firm to cut etc. I think on few occasions, they had dirty lawn mowers that caused some damage. Fast forward today, my grass is looking yellow/brown even after watering/rain. Could it be the landscaper and the machines they're using? We didn't really have "scorching" heat yet so I doubt it's drought related. I don't use any chemicals to treat it as we have kids so that's not it either.

What can I do to fix it?