This is what live chat just shared with me.
"...This applies to all Bio Sites where the "Create a free Bio Site" watermark was not removed before the change took effect. If the watermark is not removed from the Bio Site currently, it won't be possible to remove it, regardless of your plan."
So it is now impossible to remove the button. I guess I'm going to cancel that subscription and build a landing page on my website. Paying Squarespace to use my own branding colors and logo on a forwarder page does not make fiscal sense or any sense at all to me. I'm so very frustrated rn.