Goodbye 8th Year Event Goals Fix
A fix is now live. An additional goal, Earn 5 Stars, has been added. Completing this will grant the additional 500 RP to complete the reward track.
I dont believe you will have any problem even if you spent them all in 2 days. There are players that during summer rush, might spent double that amount with no problem
I think it depends if you have recently purchased them or slowly over years accumulated them free. If there is a recent purchase than I think you are OK.