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I'd be careful using 30 seconds. I use it on my deck every year to get rid of the slime, algae. Its basically double strength bleach. May cause some damage to your awning material. Here's what I use with EXCELLENT results & a LOT less bleach : A garden sprayer, a gallon of water, 1 tablespoon of liquid Dawn dish detergent, 1 tablespoon of chlorine bleach, a good soft bristle brush and a substantial amount of elbow grease. Once the top and bottom of the awning has been cleaned and dried, I spray the top with UV protectant to minimize the sun exposure and UV damage to the awning.

I spray it down real heavy; both top & bottom. Roll it up and let it sit for 5 minutes. Unroll it, spray it again real well and scrub like crazy. You don’t want to do it on a real hot day or direct sun. Don’t let it sit too long as well. Rinse and respray several times if you can’t get it all fairly quickly as the bleach may deteriorate the awning if left on too long…. I use a medium soft bristle brush on a long handle to scrub. Wear old clothes as the bleach will make them holly…

The results always amaze me

Here is what I do, following the Dometic manual recommendations, works pretty well.
https://www.loveyourrv.com/rv-power-awning-super-easy-maintenance-how-to/

I pretty much do the same thing, except since my awnings are so high,I spray the bleach solution on the outside edge and I use the remote to move the awning in a bit, then spray again (and wipe if using the protectant) ,repeat until finished.