Well, first off, it's not 12 days a year but you can only accrue a TOTAL of 12 days. Sick days are accrued at the rate of 1 every 2 months so, yes, it will take 2 years of no sick days being used to get to a total of 12. It's pathetic and one of the worst parts of the contract. Once you reach 12 you cannot add any more, so it's almost encouraging you to go sick for a day or else you're just handing the Company back two months of no sickness. We've tried in the past to get the limit increased, so that if you are sick for longer you can use those days but this fell on deaf ears. Likewise, we tried to get any days over 12 to be paid off, say at the end of the contract but, again, the short-sighted in both Management and the contract companies didn't want to listen. So there is absolutely no incentive whatsoever to attempt to hold more than 12 days sick and this just demonstrates the stupidity of the sickness system.
With that rant over, both PARC and CREW have an insurance policy that kicks in after 2 weeks and will pay you (80% I THINK) until you're okay again. So, with you broken leg (caused by braking too hard I assume....given your spelling) you'll be okay for those 3 months and won't have to take out any additional insurance.
PARC traditionally had the good loss of licence insurance( LOL) and CREW had the great medical insurance. It was the LOL that paid out for those additional days off and CREW pilots did have to pay extra if they wanted LOL insurance. However, all of that has recently changed. CREW now get a better LOL than PARC and don't have to pay a single $ for it. CREW also have the same great medical insurance that covers the pilot AND their family and no excess payment. PARC's covers the pilot only (without additional payments) and you have an excess payment of GBP200/year. PARC have a lot of catching up to do but are just dragging their heals.