I realise that some United fans have become reduced to measuring everything by the crude yardstick of money, but that's their lookout.
Kane has just had a breakthrough season, under Pochettino, at the club he's been with since the age of 11. And he signed a new 5.5 year contract just a few months ago, running until summer 2020: United could offer to treble Kane's wages this summer and he'd still choose to stay at Spurs.
Moreover, in character, attitude and motivation Kane is the polar opposite of someone like Raheem Sterling.
I think he'll stay at Spurs this summer.
But you agree that if you don't make the CL in the next year or 2 then he'll probably leave next summer or the one after that?
It's like Bale or Modric. You can keep the guy for a few years and even through a summer where everyone think he's leaving, but probably not 2 of those. This year, you'll reject any bids and he probably doesn't really want to move yet. He's comfortable, still very young, at a pretty big club and a sure starter with a great chance to score 30 goals and make England pick him alongside Rooney in Euro 2016.
If you don't make the CL in 2015-16 but he has another great season, next summer big transfer saga and maybe he stays, maybe he goes.
Levy is smart, and won't sell until he gets both a few more productive years out of Kane AND a massive fee, unless Kane demands he just take the massive fee. But the last player to turn down CL moves I can think of is Matt Le Tissier. It just doesn't happen.
I would say summer of 2018 is the absolute end of the road and should be your shining future hope, barring Spurs cracking the top 4 again. That's 3 more seasons. Kane would be 25 and desperate to play in the CL and he'd have 2 years left on his deal, so it's the last summer Levy could get a massive fee for him.