DTWH,
You make it sound like Plan A for SCA was a coherent and masterful plan, and that the later decision to put the A6 Hub at Leeming instead was merely consequential. And you also make it sound that it's purely as a result of this change in decision that units are now in limbo and scattered across Lincs ....
There were those that challenged the options of the ACSSU paper as it didn't compare like-with-like (eg Leeming good for mounting airfield v Wittering good for accomm v Scampton good for hangar space etc), and especially on the cost assumptions of regenerating SCA. But the short-sighted "solutioneering" approach prevailed and questions were pushed aside.
Based on the assumption that all would be well at SCA, other units were then put in the area in advance.
Why the change to Leeming? The real costs came to light, but only once the plan had begun. Whoops.
Had the plan been assembled properly with exact cost estimates in the first place, one might wonder whether SCA may ever have been on the books as an option? But don't stand in the way of a good solution ......