Supply is the number that matters most, because it measures how much competition your house actually faces. A lower number of months of supply means fewer competing listings for buyers to choose from, and that condition can show up in a slow February as easily as a busy May.
Your own readiness matters as much as the calendar. A house that is decluttered, priced correctly and free of deferred maintenance will outperform a poorly prepared house in the supposedly ideal month, since buyers respond to the specific property in front of them, not to the date on the listing.
The right month for your house is the one where it is genuinely ready and priced right. Get your hand-reviewed valuation from Joel Dyck.