Every ride will have bits removed and fixed at some stage, so there is no reason to panic. If they kept Corkscrew for 28 years because it started it all off, they will keep Nemesis for just as long because it propelled them onto the world scene. Plenty of rides have mid life spruse ups, so just because Nemesis has a bit taken off, there is no need to worry. If they start taking loads of bits off, or the whole ride completely, then yes, but that wont happen for a long while yet, so just relax. It will open in March with the rest of the park, and even if it is a bit delayed, they won't close it all year or even permanently. Look at the Black Hole, when that got a bit old, they refurbed it and braught it back, until H&S man came and forced them to close it or spend tones of money.