As usual, the earlier you submit your CAO application, the better. Submitting early saves you money plus it allows you to get back to studying rather than constantly thinking about what you next move will be. You can always change your mind later (for free) using the change of mind facility which opens in early May and runs right up until 1st July 2020 at 5:15pm.
The discounted online application fee of €30 applies up until 20th Jan 2020 at 5:15pm. After this, the fee then rises to €45 for online & paper applications which must be submitted by 1st Feb 2020 at 5:15pm.
Finally, late online applications can be made up until 1st May 2020 at 5:15pm but the fee for this is €60 – double what it costs to get your application in right now before 20th January 2020.