They should be OK. The caterpillars normally just eat leaves, not flower buds. The buds were set early this summer and should be OK.

Entire leaves being eaten by caterpillars is an indication of an infestation of caterpillars such as the Red-headed Azalea Caterpillar, Datana major. These caterpillars are black with rows of white or pale yellow spots, reddish brown legs, head and neck area and are 2 1/2 inches when mature. Preferred host plants are azaleas, but they may also attack witch hazel, sumac, apple, red oak and andromeda. The caterpillars feed together when young and disperse as they mature. Branches or entire plants may be defoliated. Damage occurs in late summer and fall. Look for caterpillars when defoliation damage occurs, and if only a few caterpillars are present, pick them off by hand. If needed, spray shrubs with B.t. (Bacillus thuringiensis ), a microbial insecticide that is specific for caterpillars. It is sold under various trade names including Caterpillar Attack, Thuricide, Dipel, etc. Apply sprays when caterpillars are numerous and less than 3/4 of an inch long. Larger caterpillars must be sprayed with a registered residual insecticide such as carbaryl (Sevin 50WP) or cyfluthrin (Bayer Advanced Garden Multi-Insect Killer).

Rhodyman -- I appreciate your detailed response. I'm filing it for future reference . . . Many thanks!