Can you trigger an operating system command from within Access, and run dtsrun?  See "dtsrun Utility" in BOL.

Perhaps a RunApp action in a macro, then assign the macro to the...

This may be an issue with US and UK date formats.  SQL doesn't seem to like UK date formats.  From what I can tell from BOL etc., SQL should take...

I've always converted both sides of the date comparison to CONVERT(varchar,<date>,112) to give ISO date format YYYYMMDD which can be easily compared, e.g. in your example:

CONVERT(varchar,comparison_date,112) >= CONVERT(varchar,DATEADD(year,-1,GETDATE()),112)

But I'm not...