How to load multiple scenes in one iframe?

I want to build a viewer where user can load new scene after thumbnail clicked.

I’m doing it by client.init(uid, options) but I’m receiving this warning while loading new scene to the client:

reusing a Sketchfab instance for multiple client is not supported, please create a new sketchfab instance

Is it really a must to create a new instance? Why there is no load method?