Longest time UK div in front line WW2?

[fluidwill]

Reading Slims Defeat into Victory and he mentions in passing that when he relieved the 17th Division for a much needed rest it had been in front line combat for 3 years and 8 months which he thought was a record, was it? Its a long time whichever way you look at it.

Any takers for longer in the front line? UK probably not what about other nations? Any divs on the eastern front put in years in the trenches?