Assuming they aren't Encores (and really even if they are) you would want to do any desired pruning now. Most Azaleas (not encores) bloom on last years growth, so if you wait until fall you will prune off all your blooms.

You should even prune encore azaleas immediately after their first bloom. Their subsequent blooms are on new buds.

Here is a link that might be useful: Encore Azaleas

Thanks for the info..... but I don't have any idea how to recognize an "encore" azalea.... I have lots of azaleas but how can I tell the difference?

Encore is a newish group of azaleas that bloom in the spring on old wood like other azaleas and then bloom during the summer on new wood. They are marketed as ever-blooming azaleas and do this best in the deep South.

In any case it doesn't matter since they all get pruned at the same time, just after they finish blooming.

Here is a link that might be useful: How to grow rhododendrons and azaleas.

PS

Didn't finish my sentence:

They all (regular and Encore) get pruned at the same time, just after they finish blooming the first time in the spring.