The Encores aren't continuously blooming, it's more like three times per year. Like traditional azaleas, they begin by blooming each spring. Once this initial blooming ends, new shoots begin to grow and set buds. Then blooms emerge again in mid-summer, then early Fall until first frost.

Yours may not bloom to their full potential with just 2 1/2 hours of sun.

Both drought and soggy roots could cause yellowing leaves and leaf drop. You'll need to check the soil near your plants, when it's dry to a depth of a few inches - provide water. I have a clay base too, wind, but much less heat and I water slowly and thoroughly every 7 - 10 days in months we don't have rain, for established plants.

thats correct. they bloom in sprays 2-3 times a season unlike the one you get in a standard. but you will see scattered blooms, as in 2 or 3 all the time. They need 4-6 of full sun and water water water if newly planted. You may be in to much shade. You'll stay green but not as many blooms.

Over watering will kill any rhododendron or azalea. Water in moderation. They need excellent drainage. Too little water will inhibit blooming and too much water will kill the plant.

encoreazalea.com states:

Encore Azaleas® perform best in full sun to light, filtered shade, preferably an afternoon shade. A minimum of four to six hours of direct sunlight per day is required for proper blooms. Care must be taken to prevent exposure to drought or other heat related stress conditions associated with full sun exposure. However, too shady an area can result in skipped or significantly reduced bloom cycles.