When do champion mechanics get reworked?

So im an akali one trick. I have been practicing with akali for almost 95% of my games. One thing im worried about is that her abilities may get reworked or changed. Im ok with things like changing dmg stats or cooldowns, but how often do the actual mechanics of the abilities change? For example akali w used to have no blink, now it does. Is this rare or should i be worried that this may effect my ability to climb elo?