High season I assume is summer. What...

High season I assume is summer. What is medium season?

RedWeek's Full Service Resale department use the following:

Low/Silver Season - Weeks 5-12, 44-48, 51-52 Medium/Gold Season - Weeks 13 - 21 & 35 - 43 High/Platinum Season - Weeks 22-34

What are weeks 1-4 considered? Also weeks 49 and 50?

I believe those weeks are bronze, at least that is what they are at GO.