Specialized frame warranty - cracked Alu seat tube I have a Specialized Allez Sport 2012. Which I purchased, new, just under 6 years ago in the UK. The aluminium frame has developed a crack in the seat tube, just above the brazed on derailleur mount. 

I note the newer models of this bike have reverted to a band on front mech mount. Is this because cracks like mine are common, possibly caused by a recognized design flaw? 

Whilst I understand aluminium frames have a fatigue problem it isn't the type of crack I would expect to see. The bike has done just under 10,000 miles.

Am I likely to get a replacement frame under the lifetime frame warranty. If so how long is it likely to take?
Reading the current Specialized warranty policy I'd say you are covered.

Only one way to find out for sure though - contact Specialized and ask to make a warranty claim. You will find out if they will cover it soon enough.

Unless someone here has been through the same process recently it's hard to say how long it would take.