Rhino
GB Airways are the company and they are an excellent lot when it comes to safety. You would have to ask a senior manager as to the detail of the thinking but it was universally regarded as a good measure. It meant that one of the big predisposing risk factors in tail strikes, ie pilot inexperience both on type and in general, was removed and the new guys/gals could cut their teeth on the 320 first. Personally, I thought it was a great idea as it gave the new pilots a bit of time to settle in while they come to terms with flying a big jet as opposed to a light twin. I think we all know that when you first start it can be quite daunting and a bit of settling in time has to be a good thing for all concerned. The simple fact is that unlike many other 321 operators they have never had a tailstrike and they clearly do not want to. Their success in this area probably means they have got it right. Incidentally, you don't hear many complaints from the 'cadets' about this - they all seemed very happy with the restriction.
I no longer work for them but they were very safety conscious and, unless someone can say differently, I believe that they are still applying these restrictions to new entry 'cadet' pilots.