Bitlocker Recovery after BIOS Update

Yes, reverting will probably skip the Recovery Key prompt, but you absolutely must back up your Recovery Key.  If your motherboard or TPM had failed and you needed a new one, you would have no recovery mechanism at this stage.  I personally store my key in my LastPass vault so that I can easily access it from my phone when I don't have access to a PC, but if you don't use a password vault, then just email it to yourself or something.  There's a reason the BitLocker wizard forces you to back it up during setup and tries to prevent you from storing the key on the drive you're about to encrypt.  Take it seriously.