The Flag

What happens to the Union Jack and even the Australian flag if the Scots vote for independence   (and here)?  There was an article in the Australian about this (sorry about the paywall), but the essence was that if Scotland became independent, then logically the St Andrew's Cross would be removed from the Union Jack.    Then the issue would arise as to whether a consequential change would be made to the Australian flag.    Of course, this is all entirely speculation at present and involves several layers of "what ifs" ......

The article in the Australian suggested that the Australian flag could end up looking like the flag on the far right.  Well, maybe, but doesn't the blue background come from the St Andrew's flag?    Why would this be retained?   The stripped down Union Jack - assuming that this came about - would presumably have a white background because the two remaining components,  St George's cross and St Patrick's cross, both have white backgrounds. 

One possibility would be to take the opportunity to change the Australian flag, but the big question is, to what?   Please, let's not move away from the present flag until we know what we'd get instead.   And for the record I don't much like the design being promoted by one group (left).