I had a site from years ago (2006) that I think was under some penalty as it was once ranking quite well but then I made a national site which took over. Eventually black hat tricks from my national site after working until 2013 fell too.

After re-building the national site and starting to see positive results, I ordered my web firm to re-direct my original site to the new one. Back then I know nothing about back links and link juice but I was monitoring a bunch of words with positionally which suddenly dropped on the same day.

Bad results continued for at least a month until I submitted a disavow for both my original and national sites. Since then they have improved but still not as good as they were before the redirect. I also think that the disavow may be very slow to take affect as movement is gradual.