I see leaf edges that are browning and that suggests insufficient watering. I also see some leaves yellowing but the leaf veins remain dark green; that is a sign of soil being alkaline. Leaves that are all yellow, including the leaf veins, suggest lack of some soil minerals or too much sun.

Begin a regular watering program to try and maintain the soil evenly moist at all times. If you let the pot get dry then wet and dry again, this uneven watering will result in this problem. Depending on local conditions, you may have to water multiple times a day. To tell if you need to water, insert a finger into the soil to a depth of 4" (about 10cm) and determine if the soil feels dry or almost dry. If it does water the plant until you see some water coming out of the exit holes at the bottom (I assume the pot has several holes, right?); when you see the water coming out, stop/pause watering for several seconds and then water again.

Windy locations near the coast like yours may make the soil dry out faster (the plant soil already looks dry in the picture) so move it if necessary to a place where it gets morning sun and where it is not windy.

Amend the soil to acidify it. Use greensand, aluminum sulfate or garden Sulphur. You can also use iron-chelated liquid compounds sold at most plant nurseries. The liquids will reverse the signs of iron chlorosis (yellowing of leaves except for the leaf veins, which remain dark green) faster than the granular/solids.

Make sure you are fertilizing often too as potted shrubs need water and fertilizers more often that those planted in the ground. I do not see fertilizer pellets on the top of the soil so, if you are not using liquid fertilizers then make sure you give it some fertilizers. You can use slow-release, general purpose fertilizers of your choice, organic compost or composted manure.

If this potted plant's watering is too difficult to handle, consider planting it in a location that gets morning sun until 11am more or less, gets water thru drip irrigation, soaker hose or a sprinkler system, is not windy and where the soil drains well.

The best news is that you are basically in the Fall for all practical purposes. Soon, the plant will go dormant and the foliage will change color, dry out and brown out soon. At that time, you can remove all the leaves. But remember that invisible flower buds have probably already developed at the end of the stems so be careful where you cut. You can safely cut the leaves at the petiole, the little strand that connects the leaf to the stem.