Check out QRH 4.06
For a 319 at 58T driftdown distance and time from FL370 to FL276 is 360nm in one hour. In other words, probably enough time to escape the typhoon before you hit the top.
A321 at 72T is 380nm 70 mins to FL220 from FL 350. Clearly you would not want to be in this situation.
In other words, flying 7000+ft over the top in a light aircraft is probably not a problem. Flying 2000ft over the tops in a heavy aircraft is taking a chance.
Sadly, trying to get your flight ops dept to understand this may not always be possible.