Having the VCT get sticky is apparently very common.
But it's usually in the retarded position.
The exhaust cam is supposed to be retarded when the PCM tells the VCT solenoid to send oil pressure to the VCT cylinder. A spring returns it to the advanced position. When it's gummed up, it usually fails to return to the fully advanced position.
You need to make sure the VCT solenoid is working, and that the timing belt is really on correctly.
It is common for the belt to be put on while the cam is retarded by sticking, in which case it may at some time become too advanced by freeing up.
The only way to tell is to have someone who really knows what they are doing check it.
If you were to try it yourself, I would remove the valve cover and use the hex on the exhaust cam to see if it is returning to the advanced position, and use a timing light on it to see if it retards while running. This is not something to be tried lightly.
An oil flush is a good first step to be sure the system is not gummed up.
