if you try and import the column as a date field, it will be cleaner for any future grouping
in the list of "SETS" in Load Editor, change to SET DateFormat='DD-MMM-YYY';
this should import your column as a date field.
you can then use MONTH(columnname) as well as YEAR(columnname), WEEKSTART(columnname) etc.
Many thanks to all the replies - and so quickly aswell.
Thanks to you all, and just one more thing if I may? - is it straight forward to expand it to longnames? at the moment it is coming out as Nov - can that be expanded to November?
Thanks Again - I will mark Andrews as the correct answer.