Hi Chris,
Financial year has no specific relavance for the company I work for, can't say for all or smaller companies. All our books go to calender year. Always best to try and get a deal at the end of a month, especially end of 1/4 or as you say year; as targets are based around these periods.
When you go in towards the end of a month and are asked a tell tale kind of question, early on, like "when you are looking to buy" or "would you consider delivery before the end of the month". Give an answer like "imediately/yes if the price is right". Answers like in the next "6 months" or other non comital answers are a natural defense answer but don't excite sales guys.
Mark.