Shoshana, what is in modern Hebrew the future, e.g. ehyeh, had a
totally different sense in biblical usage: it was the "imperfect", that is
an action that was not concluded ( as against the "perfect" which refers
to the past. Both of these senses can be further refined as you may have
seen in recent exchanges on this list)
Thus imprecise as it is, the only possible translation of Ehyeh asher
Ehyeh
is: I am/will be whoever I am/will be.
Uri Hurwitz