That looks good to me. I'm in another country, so brands don't all line up.
In the cyst, the parasite is safe to feed away. Increasing the heat will speed up its life cycle, but you have to be sure the fish you have can handle the warmth. Some of mine couldn't.
A quicker life cycle makes the parasite reproduce, and to spread it has to break the cyst. That's when the med is very effective at killing it - as it fans out in search of new victims. Warmth also reduces the time it has to do damage. Older sources suggest salt, but its function is to make it hard for the parasite to burrow in as it's a skin irritant and the fish will produce large amounts of body slime to deal with the discomfort. The parasites find it hard to get through that defence.
I prefer the mutagenic dyes as they do less damage to the fish and work more rapidly. With such a bad outbreak, you have no guarantees any fish will survive. As a hobby, we have a weird mindset where people blame the med because they got a med in too late to deal with a killing parasite. Uh huh.
I haven't had ich come in for a very long time now, but I always have the meds here. If you treat it at the first spot, it's nothing. But once it's on the loose, it's trouble. As you noticed, it likes to appear on Sundays after the shops close.
It's carried in on newly acquired fish.