According to our code team, the Reward stages are coded to be shown as completed by the game based on the amount of towers killed. So, due to this issue you would have killed a lot of towers more easily than normal, and therefore the game thinks you were placed at a higher stage. So when we fixed the issue and you logged back in, it assumes that you being at a higher stage correlates to having those stages Rewards as ‘Collected’.
Additionally, if you didn’t ‘Collect’ the rewards before the fix you would have to kill enough towers to get up to that stage again (this is normal, as again, we changed the Invasion mode to go back to what it should be).
Please PM me if you did collect the rewards before we corrected the easy-requirements issue, and what stages you collected, and I’ll double check the logs of your game for you.