Certain rooms and furnishing require the guild hall to be at a certain expansion level before you are be able to purchase them. Is this an one time requirement which only needs to be met at purchase or is the expansion level a requirement for the use of rooms and / or furnishing?

For instance the guild training hall requires the guild hall to have atleast a level 4 expansion/floor. If say after purchasing the training hall it is decided to remove the 4th floor is the training hall still available for people or becomes it inactive? Or does it disappear forever and if you want it again do you need to repurchase it?

The same question applies to furnishing. Flying and wandering snipes require the last and 5th expansion of the guild hall. What happens if these are bought and then that floor is removed? Do they still durdle around the guild hall or do the disappear? And are they removed forever if so or are they just inactive until the 5th expansion has been purchased again?

Couldn't find the answer anywhere so sorry if I missed it, but I guess these are interesting questions in relation to upkeep cost and investments guilds might want to do.