I generally find 'list our best 22' conversations absolutely moot until after the praccy games - particularly with the sheer volume of youth in the side now. It is way too hard to assess the output of the draftees and overall improvement of the second year players until the pre-season is in full flight and there's been some actual footy played.
Yep the point being if a best 18 is unavailable, an interchange probably can step in, but the new best available is not usually #23 on the list. It depends where the hole is created