will i not be able to use - from gold to silver

Yes (same answer for both character slot questions):

I am 90% certain that you will only see 4 characters, but the others will still be there. They are listed alphabetically, so the first 4 alphabetically should be the ones you see and the others will remain hidden until you go gold again or buy a character slot. You can pay 800 DB Cash for 1 additional character slot, or 2000 for 3 (I think you can only get 3 this way). You can also get a couple character slots through the loyalty tokens (also limited to 3 I think.)

Silver was a specific purchase in the station store. For a one time 500 station cash (at the time) purchase you upgraded your account to silver, with all the related benefits.

I don't think that has any correlation tbh. Every account that I have that has ever been all access before or after they did away with the old bronze, silver, gold packages has defaulted to "silver" status on character select when they are not all access. Only one account which is my main account has ever used one of those old expansion account keys via discs. The other accounts are way to new and were created after they went away from discs and just have people DL the expansion. If you are suggesting the game card account keys I don't think there is any correlation there either because only my main account has ever used those when they were available. I have used both a mix of krono and paying for subs on my alt accounts though. All of them have been subbed for longer than a month at a time so maybe that one variable to consider? Maybe if people only sub for 1 month it wont give them silver status but if they sub for 3, 6 or 12 months it will?

Yes and no. Silver was also obtained by being gold status and if you decided to go to ftp you would default to silver. None of my accounts ever paid the 5 dollars for "silver" status yet when ever one goes back to ftp they are "silver" status at character select and get all of the same benefits as someone got paying the five bucks.

These are the bodies of two emails I received from Customer Support last April (2017). There is no personal information, and it looks like safe information to share, so I hope I don't get banned:

And after pointing out that I had two nearly identical accounts that were treated differently (only difference was when each account went Gold for a month, but both had gone Gold within the previous 6 months):

Please don't ban me for trying to clear up confusion!

Silver was a $5 one time payment several years ago. Some of us, just before f2p, suggested that Silver become $5 per month, with the limits of Silver. Didn't happen.

About the time of f2p, there was a limited time to convert all of a player's f2p accounts to silver. I did so. After that, when I stop All Access on an account, I have limited finds, I go back to silver, instead of f2p. And I haven't had a problem getting to all characters.

Thats because some were 'grandfathered to silver' instead of f2p.

I think anybody interested in the history of Silver status should compile a list of official announcements. I think everybody's memories are failing (we're mostly an older crowd), and the memories definitely appear to be conflicting.

But I do know what customer support told me last year. Please try it and report back with your findings! I bet (based on my own personal experience with multiple near-identical accounts) that we will receive reports with different results.

In my experience, the characters that will be available when you go F2P will be the most recent characters you last logged in on.

As I have already stated I have accounts that were created after they did away with the old system yet these account have defaulted to silver. No idea why and honestly I don't think anyone knows the exact reason. Maybe it was a coding error on their part where it was still granting people silver status if they went all access for at least a month or maybe this was intentional to try and get people who missed out on paying the 5 dollars for silver to fork over 15 bucks for a month of all access and then default to silver afterwards. When I eventually get around to evolving my buff bots AA's I will post my findings to see if they also default to silver status or just go back to ftp status.

I vaguely remember there was a time limit to get them set to silver, without paying the $5. But I could be wrong.