The "retrospective" bit applies to changes to regulations already in existence as at Dec 2004. The MSC rules are new legislation as from April 2007 so are out of scope.
Anyway it would be horribly difficult to apply the MSC rules retrosectively. For example, you would immediately claim that it was the MSC that owed the money, not you, since they should have been paying you at full rate, not via divvies (which they should, TBH, but you know what I mean). The MSCs - some of whom no longer exist of course - would counter sue saying they wee merely following you demands... Overall, probably not really worth anyone trying.
Anyway it would be horribly difficult to apply the MSC rules retrosectively. For example, you would immediately claim that it was the MSC that owed the money, not you, since they should have been paying you at full rate, not via divvies (which they should, TBH, but you know what I mean). The MSCs - some of whom no longer exist of course - would counter sue saying they wee merely following you demands... Overall, probably not really worth anyone trying.


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