Reasonability is always defined by the circumstances
Whether 90-120 days or 15-30 days is reasonable is always indefinite and, in your words, something similar to an opinion. It depends upon the context. Three or four months might be reasonable for a product, say, that retains commercial value for 10 or 15 years, like an automobile. It certainly wouldn't be reasonable for a quart of milk that would spoil in that time. A cell phone lies somewhere between those two extremes. If cell phones--or more importantly, their software--lose their commercial value in 24 months (is that more or less correct?) I would suggest something closer to the shorter end of that continuum would be closer to the "correct" answer. Whether it would be worth it to litigate would depend upon whether it would have important consequences in other cases as well. It does seem that this is an invitation for abuse if the issue is never resolved.
Whether 90-120 days or 15-30 days is reasonable is always indefinite and, in your words, something similar to an opinion. It depends upon the context. Three or four months might be reasonable for a product, say, that retains commercial value for 10 or 15 years, like an automobile. It certainly wouldn't be reasonable for a quart of milk that would spoil in that time. A cell phone lies somewhere between those two extremes. If cell phones--or more importantly, their software--lose their commercial value in 24 months (is that more or less correct?) I would suggest something closer to the shorter end of that continuum would be closer to the "correct" answer. Whether it would be worth it to litigate would depend upon whether it would have important consequences in other cases as well. It does seem that this is an invitation for abuse if the issue is never resolved.