Err... huh?
The initiative change is only relevant for the next round.
And of course the condition has not yet been fulfilled, but it is fulfilled right after readying, since the trigger condition is currently valid, because it triggered the first ready action, and the action was interrupted at that point, so it still is at the same point when you go back.
For example, if you use the trigger "if an enemy is attacking me" once an attack starts, your ready action triggers. When your ready action is completed, the enemy is still attacking you, so if you readied an action to trigger "if an enemy is attacking me" then this will immediately trigger.
But even if the same trigger would not work again, you could surely find a trigger that will trigger immediately (i.e. if the sun is shining, or if it is the seventh of the third month, or if I am alive, or ... ok, I guess it's clear already). That's really the smallest problem there.
Bye
Thanee