I know everyone really wants the Yeti to run in "A" mode again, but I hate to be the bearer of bad news - it ain't going to happen. The Yeti himself is fine. He has had some hydraulics issues now and then but all very fixable. The main problem is not the Yeti himself. It is the concrete base he is attached to. You need to know that he moves with the same amount of trust from a 747. When the attraction was built, the concrete based was not poured correctly and was not cured properly either. After about a year, the Yeti started causing cracks in the base. This is a MAJOR safety issue (imagine Yeti crashing through the tracks as he falls from his base). The way Everest was constructed, all of the different phases were assembled in interlocking pieces. To repair the base, the attraction would literally have to be disassembled. The cost of the repair plus the loss in revenue from park goers would be tremendous.
Some may wonder how I know this... I am a former Imagineer.