Thanks to Ryan Littlemore ( or should I say Littlehair , the only guy who has less than me !) for reminding me that of course the Japanese financial year ends 31 March and traditionally we can expect corporates repatriating yen back home. Some years it has had a particularly heavy effect on the USDJPY, from memory last year was not so much as the BOJ were steering corporates away for better times.
We are seeing exporters selling regardless now but I feel it will merely slow any enthusiastic rise for the time being.