Duration cannot be inferred from the bottle alone
The extrait designation may indicate a concentrated presentation without guaranteeing the same number of hours for every fragrance and wearer. Formula, application and wearing conditions contribute to the perceived result. Amouage Interlude in extrait form provides a documented reference, but it cannot predict the performance of an entire category of perfumes on its own.
Keeping a useful wearing diary
With a Maison Crivelli or Guerlain extrait set, record the amount applied and a few observations at intervals during the day. Distinguish what you smell close up from what others naturally notice, without repeatedly adding sprays to check. Comfort and enjoyment during actual wear, observed on several occasions, remain the most useful indicators for your choice.