Important to understand that CD&R own 75% of CHC and it is unlikely they are changing their investment (ie selling shares).
The drop in stock price could well be the other investors who got duped by UBS and Barclays (acting for First Reserve, the previous owners) into buying crappy stock and finally calling it quits.
Also worth noting that while CHC and BRS do the same job, CHC are relatively stronger in exploration contracts and BRS are much happier with long term production ones. Thus if OilCO decides to stop/ delay exploration, CHC are more likely to be hit. That said, if Oil CO decides to pick up again in 6 months when oil is $80 bbl then CHC is more likely to see the benefits.
CHC is royally screwed though. I think they (CD&R) will sell off the bits of the business which are hard work and keep the bits that are working.
Getting the stock now at 10c on the $ from 12 months ago is an interesting investment option for sure.