Wait the end of the flowering, always.

Here is a link that might be useful: lovcam

The website lovcam is in a foreign language that I can not read.
In this area you really don't need to wait until they bloom (this is the same here for azaleas and "rhoddies"). What I really need to know is can I cut them way back (not "thin")by about half and will they still be able to bloom?

Yes they can be cut back as severely as you want, but you will lose this season's blooms. (They bloom in winter.) And blooms will be sparse the next 1-2 years as the plant regenerates its foliage -- depending on how heavily you cut it back.

My mom has 80 year old camilia bushes - 7 of them in a row. They were planted by her mother. Now she is wanting to "prune" them - they are very healthy bushes (trees). Any advise on this? I think she should leave them alone.

Depends on what she has in mind. For example, she can prune branches that cross and grow towards the inside at any time.

my camillias are in a narrow border white and pink about 3 foot high no more room in garden shall i prune pink one looking poor and small buds this year