I don’t think having a second or not has anything to do with when a foreclosure goes up for sale. Obviously making sure the home is ready for sale is the first thing, tenant/owner eviction etc… Other more obscure things like IRS right of redemption would be another. There is a 120 day right of redemption. Any other legal matters may delay the home going to market as well. Finally there may be issues like open permits that need to be dealt with and the investors that now own the property may not want to deal with them at present. So beyond those sorts of issues all of them should theoretically go for sale. Now it is improbable this happens so why some go and some do not at that point is a good question but doubtful that a previous second had anything to do with it.