I've been seeing lots of them the last 2 years, have probably caught a couple dozen now, 1 of those on the Vedder. It seems some flows have them way more prolific than others. One of the island flows I've been fishing the last 3 years has a bunch, probably 1 out of every 5 steelhead are 2-3 maybe 4 pounds.
No doubt they are steelhead with how they look, even caught a couple with sea lice. Extremely stunted fish that are around 2-3 pounds. I have heard to them referred to as "half pounders." Apparently some island rivers back in the day had lots of them. Not just jacks, but jills (both of the fish pictured appeared to be does).
For size scale, that is a 2/5 spoon approximately 2 1/2 inches long.
Lastly, to answer your question... yes it will come back. Steelhead that go back out will return larger the next year. Typically the 5-6 pound steelhead you see returned after a year in the salt (technically 1.5 years, out in spring and return the next December-April). Rivers like the Stamp have a large component of those. Larger fish are typically repeat spawners. Some will come back up to 6 times. These hatchery fish are probably much like coho jacks - coming back the same year they went out (so ~8 months at sea). Can't be sure of that though, would need to see some scales off of them.