Good morning! Love the color change because I know the direction it means you're heading! I also think it means your filter is chugging away nicely helping get some of the iron out. When your slam is done and you're not losing chlorine overnight I will be happy to assist you on that front.
In the mean time, I'm confident you'd be fine/safe (eg not bleaching your liner) if you added a jug of bleach in a.m. Then another again at night to maintain because while store tests aren't accurate they rarely come up with high cya when there isn't any (usually their tests underreport when near 100) so I'm pretty sure you have high cya which means a higher shock/slam value than where you're at.
A gallon in your pool of 8.25% bleach at 25k gallon pool will get you about 3.4 ppm of FC. So adding that much day and night is a very conservative coast for a few days. (That from the pool calculator.)
One thing you might consider while you wait is a partial water change, eg. 30% to help get your cya lower so that you can use less bleach when you slam. I highly doubt you'd get it too low given the range of cya readings from the store

...and it might speed up your progress too/make it easier when you finish up with a slam. Just be sure to leave a foot or so in the shallow end and for that matter add water at the same time to prevent any floating liner issues. Dilution is the key for high cya. (I realize you have the party. I mean post-party if you're of a mind to keep moving on it.)
If you haven't already, take a peek at the CYA/FC levels link in my signature and you'll see the difference in the chlorine levels required to sanitize between optimal and high cya levels.
I'm so happy you're turning the corner on this...the summer ahead is going to be the best birthday present your daughter could get