Yes it's OK to eat turkey after the use by date.
As long as the turkey has been frozen the turkey will remain safe to eat for up to 2 years past the use by date.
The use by date is just a general guideline as to the freshness and quality of the turkey and it's best to eat the turkey before or at least on the use by date so that it will be much fresher and have a better taste to it.
However you can keep turkey frozen for 2 years and longer and it will remain safe to eat.
The freezer temperatures keeps bacteria from growing on the turkey so it will be safe to eat.
As long as the turkey smells good and has not really slimy feeling to the turkey then it's safe to eat.
If the turkey smells bad or has a really slimy feeling to it then it should be thrown out.
The turkey will last for up to 3 days in the refrigerator and up to 2 years and even sometimes longer in the freezer.