So are these filter cartridges or membranes? Completely different items, with different implications. Filter cartridges are designed to be replaced at intervals, membranes usually are not.
I think complaining when the water is off (completely) and we are told that will be the case for several days, following on the tails of a massive price increase, is not unreasonable. Besides, I think a lot of "non regulars" have also objected to this.