Starting a sentence with “Umm” always annoys the people who read it. You might as well start with “You idiot”.
And it’s particularly bad of you in this case, where the writer explains in great detail why this is problematic — because they had a project that had been working for years which they did not change, because they had no warning that this billing change was happening, because once they found out that this was happening, they had no way to observe what was going on.
Heck, an extra $24,000 a year in expenses for a hobby project is probably calamitous for most people in the world.
Try being polite instead of piling on someone who’s already having a really bad day. This might prevent strangers on the internet from forming a bad opinion of you…