Bank no longer supported?

Which Edina? MO or MN?

And, I tried scanning FIDIR.TXT, which records the banks that have connectivity with Q, and couldn't find any reference to that bank when I search for Edina.

Normally, if the bank (NOT Q) had decided to drop connectivity, the entry would have been changed to zzz-Citizen (etc). But there was no such entry.

You might try contacting Q Support, via the link at the top of this page, to see if they know about this.

Downloaded OFX files are for old MS Money. QFX files are for Quicken. Quicken will only import a QFX file if the financial institution is a participating partner.

Sounds like your FI decided to not participate.

Whatever financial institution name you are currently using appears to have been removed from the list of supported financial institutions.
Deactivate all your accounts with Bank of America
Backup your data file and restart Quicken
Using Tools / Add Account (or click the "+" button in the Account Sidebar title) locate and select Bank of America from the list. Pretend to add all new accounts and identify yourself to the bank with your existing ID and password.
When you get to the list of accounts found at the bank, instead of adding new account registers, carefully select LINK and point the account at the bank to the correct, already existing Quicken account register. Repeat for all other accounts with BofA
After connection is complete, some cleanup may be necessary. The download process will download the last month or two of transactions from the bank. This may create duplicate transactions.

Unless the financial institution is blocking it someway that I am not aware of, Simple vs Complete is a user choice that is changeable when you edit the account from the Account List: