It must be when you are creating a new listing rather than revising existing.

Because I don't have the option you show when I am revising an active listing.

I'd like to be able to add this option to our existing active BIN listings as it appears we meet ALL the Criteria. Just that we never saw this checkbox when we were creating all our listings. And they are all GTC listings now.

Next time we are creating a new listing I will look out for it.