Such an always-alternative doesn't exist. ß was changed to ss at the end of short syllables, that is all. I think there is a rule to always use ss instead of ß

Such an always-alternative doesn't exist. ß was changed to ss at the end of short syllables, that is all. I think there is a rule to always use ss instead of ß (and ae instead of ä, etc.), when ß is not available. But that wasn't introduced in 1996, that is way older and less relevant today than it used to be. Gruß, stkdump