Audible stopped offering Audible Plus - no credits membership?

I just went to confirm my membership was 'downgraded' for the next month, since I have a few credits to use and don't need any more right now.

I remember the options were I could do a $7.95? for just Audible Plus access with no credit, $14.95 per month for the 1 credit and Plus access, $22.95? for a credit every other month and Plus access, then other options above that 1 credit per month. But looking at my options today in Audible the no credit and every other month credit options are gone. The cheapest option is to select one book per month from their collection that you have access to as long as your a member. Which reads to me you have access to Audible Plus but it's limited to one book per month.

Is this right? Who is going to pay $10 per month for Audible just for rights to access one book per month? I'll just pay for Spotify where I basically get the same, plus music.

Edit to add: I understand how the credits and Plus catalog work, that wasn't my question. I was asking about the change in membership options. Thanks to those that responded to my question.