Remove page limit if I intend to transfer hosting?

I have paid for a site plan for the ‘old site’ Site A. It is currently live and hosted with Webflow.
I intend to make a ‘new site’ Site B, & transfer hosting plan from Site A to Site B, using this method: Transfer hosting between projects | Webflow University
I am starting to create Site B. However, there is a page limit of 2 pages because it is still considered a ‘free’ plan.
I intend to have Site A live & hosted until I have completed Site B.

Am I right to say that:
If I want to remove the page limit, I need to pay for 2 site plans concurrently?
Any other way around it? In the end, I only want to have Site B live but until its done, I want Site A live.

Here is my site Read-Only: LINK
(how to share your site Read-Only link)