The real deal isn't the +-40 mins sell, but the fact that when you go into the market, it lists only auctions ending in the next few minutes (on my server it's around 5-6 minutes or around 25 auctions).
That being said, it means that when i put a player in auction, to have a chance of selling him, theses factors are needed:
- a manager interested in the player i'm selling
- This manager going to the market in the last 5 or 6 minutes before the end of the auction. (that is the real problem, managers can't look at the market 24hours a day, most of us go there every 2 or 3 hours to see what is going to be sold in the next hours...)

It's just too short !!!
I'm okay to reduce the lenght from 2 or 3 hours to less then one, but please, let the managers see ALL auctions for the next hour, so that we can put a token on those, not only if we get luck to come at the right time...
That's why it's so hard to sell players from now.