The higher you estimate the more you will lose weekly as they will take into account what you could potentially owe them by returning to work. So if you estimate the whole year, say you might get nmothing by the time they withhols what you 'might' owe from what you are entitled too. However, if you estimate correctly you may still get some.

It's really up to you whether or not you need the money in the interim. Sorry in a hurry i hope that made some sense.