Switching from regular blended oil to synthetic oil for your vehicles engine is perfectly okay and it's even okay to switch back and forth between regular oil and synthetic oil.
Synthetic oil blends are simply a mixture of synthetic oil and regular oil and it will not harm your engine to switch from regular oil to synthetic oil nor will it harm your engine to switch back and forth between synthetic oil to regular oil.
Synthetic Oil will help protect your engine much better as well than regular oil will especially if your engine has a lot of miles on it.
Your engine will last longer when using Synthetic Oil than it will on regular oil especially if the engine has high miles.