Red Dog,
That's another point missed by many. At least you Canuks have a tax break. Brits have to either spend more than 270 days a year out of country or pay full tax on eveything, so the companies arguments about a tax-free salary mean nothing. I hear that Bristow hoped that the chance to work 8/4 may have attracted quite a few people because of the tax problem, but as they didn't offer proportionately more salary for 8/4 (as NEO says, only 20% extra for 30% more work) they have had only a few volunteers.