Good to hear your back greenleaf4u!
All my sites in question came back much stronger about a week ago and I got a big surprise from a site that was sand boxed 8 months ago. It appeared on the first page for it's keyword
A lot of my sites just reached the 15 month age mark, so I think google basically accepts them all as good sites now and was just finding their rightful place in their rankings.
I have about 10 sites in the 8 month range and they appear on the first page for 3 weeks then disappear for 3 weeks like clock work, so I am thinking once they hit that 12 to 15 month range they will solidify also.
Take into account I have not done one thing to any of these sites since the first month I made them. No backlinks, no keyword change ect.. nothing, all seo was done the first month or 2 after making the site, so I thing the age of a domain is just enormous to google.
I also have another group of sites I do daily seo to, but they drop back in the rankings fast if I do not keep up with the back linking. I need to figure out how to get them A few strong links, like the sites mentioned above.
I think the moral to this story is, you need age, strong permanent back links from authority sites and just sprinkle some grey hat techniques for that final push or as needed, if the goal is to be in place for years.