In regards to relocating your plaza: I discovered all events are tied to the COBBLESTONE, not to the Plaza Tree itself. All other fruits will grow into normal fruit trees. Once you change your native fruit to cherries, however, you can plant perfect cherries at will and they will grow into perfect cherry trees as they should. You must now manually cut down all the peach trees and replace them with cherry trees if you want cherries to be your new fruit trees. However, all of your peach trees in town will REMAIN peach trees (and yes, if one of them has the perfect peach on it, that tree will remain with the original perfect peach on it as well, and you can shake the tree and harvest the perfect peach if you wish - however, planting the perfect peach would now cause it to produce a normal peach tree). Everyone will now acknowledge that the town fruit is cherries. If you change your native fruit type to cherries, the change WILL go through. So, say you just started your town and you have peaches and want cherries. So, town fruit can be changed at any time without any ill effect I have found.Д¬hanging your native fruit type DOES NOT CHANGE ALL OF YOUR TOWN TREES TO THAT FRUIT. If changed before you talk to Isabelle about the town native fruit, she will indeed state that the new fruit is the town fruit. I also confirmed that changing your native fruit in the HEX also changes your native fruit in the dialogue with all NPCs and characters even if changed at the very beginning of the game when you are still talking to Isabelle about advice for living in town.

(That order also mathematically explains the probability of getting apples or cherries as your town fruit when generating a town.

Animal crossing new leaf fruits