Most readers agree tarot is bad at "when". The deck has no calendar.
If you must ask timing, use these soft conventions:
- Wands — fast, days to weeks
- Swords — moderate, weeks
- Cups — slow, weeks to months
- Pentacles — very slow, months to seasons
- Majors — archetypal time, not clock time
But honestly, a better question than "when" is "what needs to happen first?" You'll get a much more useful answer.