New and Old, Douglas Fir and Cedar

We live an hour north of Montreal, Quebec in Canada. The questions are for two separate decks.

A - Front Porch, partial shade, rough Douglas Fir, new wood bought last year and stored in the garage since then, deck planks (2x6) still to be installed.

B - Back deck, full sun, red cedar, plenty of mold, mildew, lichen and moss, part of this deck is from last year and around the pool, the other part of the deck is 10 years old was protected with Cabot Neutral 8 years ago, was never cleaned or maintained since.

We are thinking of using Armstrong Clark transparent or semi for all the outside Douglas Fir and Red Cedar. I know that the final color will not be the same depending on the original wood.

Questions:
1- Do we need to clean and brightened the Douglas Fir that was never exposed to the elements prior to staining?

2- Is the Douglas Fir dry enough to stain now or should we install the planks now and wait until next spring to stain?

3- Since the Douglas Fir planks are not yet installed, should we take advantage of this fact and stain all faces of the planks before installing them?

4- Can we use TSP to clean the red cedar prior to staining it? We have used this product in the past on a PT deck and it worked like a charm.

5- Will the Armstrong Clark be able to resist the pool water?