Darkness Beyond Time (Dimensional Nature)
We know that the Darkness Beyond Time is the final resting place for discarded timelines overwritten by time travelers. But does the Darkness Beyond Time exist for all dimensions, or does a DBT exist for each? This question hinges on a couple factors. Specifically, if there are infinite dimensions and only one Darkness Beyond Time, the Time Devourer could not possibly devour the infinity of the space-time continuum. However, if there are only a finite number of dimensions in the multiverse, this problem is moot.
Ultimately, this problem rests on the interpretation of Belthasar's statement that the Time Devourer will destroy all space-time continua. If taken fundamentally, it means the multiverse, though if taken conservatively, it only means the Home and Another Worlds will be destroyed.
If you think that if there is only one Darkness Beyond Time and as a result, infinite chances of a Time Devourer forming and destroying the universe, remember that as evidenced by Serge, there is also a persistent chance that something will arise to challenge the Time Devourer and prevent it from devouring space-time continua.