I really wanted (needed) this to work, but it didn't help my load times, at least not that I could tell. The support team was very professional and friendly but I couldn't detect a difference in performance even after their help. I ended up just turning off "Quick Shop", which made a significant difference in load times. I think I'll save my $19/mo and just turn off Quick Shop.
I am Sophia from Swift ‑ Page Speed Optimizer Support Team. Firstly, I sincerely apology for any inconvenience caused to you.
Regarding to your concern, there may be a misunderstanding here. With plan Premium (19$ per month), you will have 1000 free images per month, it will renew every month. You don't need to pay more for optimizing images. However, it is because that you are still in trial period, you will be given only 100 images for experiencing the app. After 7 days when the trial ends, your image balance will be added 1000 images more.
Also, our Dev has analyzed on your store performance and come up with some useful suggestions to improve your store speed. My colleague, Maria, is following you in email to support you further, please kindly check and get back to us so we can help you further.
Swift ‑ Page Speed Optimizer Support Team