Silvering of foliage can appear on infected trees soon after petal fall. The silver leaf symptom is due to a separation of the upper leaf layer from the rest of the leaf tissue. This separation is caused by a toxin produced by the fungus. The silvering is not always present each year in infected trees. If you cut through branches or the trunk, you will often see that the wood is stained and decayed.
Infected trees can decline for years.
It seems every few years we have conditions that cause more symptom expression and this was one of those years.