Just for fun, go to google and search your site with this query: site: edcforums.com
I get only about 40k of results. You appear to have about 80k of threads. This is not good. But please, be stubborn and don't listen to the advise that has been given to you.
I am actually asking the same things in multiple places and each place the information I get is contradictory. The next thing is I didn't have the plug in installed before so I am not getting information that I can use from it at this time.
While the information that I can get might not be accurate it seems to match up fairly close to what actually happened compared to what I see internally. I cannot use data from plug in tools from other forums so I can only use the information I can get to. The forums that took a drop are indeed getting fewer people also.
I cannot follow most of the advise since.
1. The Google An was not installed before this happened.
2. I don't use the Facebook, and Twitter integration. I used Facebook integration for about a day a couple of years ago and that did nothing but bring the people I didn't want. Checking that will not help.
3. I have not changed anything on the forum in a long time.
4. Some of the advice I don't think I can follow because I never did anything deliberately SEO related.
5. I did the DNS and other checks people have said the try and they came up OK.
6. I cannot check with the hosting company until they open on Monday.
7. While the things I have been looking at are flawed there is a close relationship to what I am seeing with the stats inside of Xenforo. No one has suggested any tools to use to check other forums that I know are also down in activity.
It is not that I am not listening, I am missing what else to check since the tools suggested will not go back to when this happened.
One thing that is showing is the number of visitors increased for the first time in awhile increased today and the day still has three hours left in it. Sunday should not beat Thursday but it is.