OK, well after some further analysis, the issue of selectively suppressing superfluous retro entries won't actually start to become real until April 2013, so in that respect I have a breathing space.
I did manage to create a udf that seeks out specified retro entries with a source start date older than a specified threshold, and thereby producing a contra-value to negate their effect. That seems to work a treat. But too late to include it in our solution for this coming April.
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L&K
CT
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