Wayback Machine:

Snapshots usually become available more than six months after they are archived or, in some cases, even later; it can take twenty-four months or longer.  The frequency of snapshots is variable, so not all tracked web site updates are recorded. Sometimes there are intervals of several weeks or years between snapshots.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". How long are intervals between cases?
unanswerable