Home Forums Hunting & Shooting Hunter's Campfire Vaccine expiration date?

I work with a guy that is planning on traveling to Greece for vacation with his wife on October 1st. His vaccine card doesn't say anything but he got some kind of covid passport app on his phone and it registers your covid shot dates. It says his shot expires. actually has an expiration date, of 9/30/21. Six months after getting the shot. So he thinks he will have to get another one in order to travel to Greece. Has anyone else seen or heard anything about this?
Please keep on topic. no comments about going to Greece, hating covid passport, all that other crap. just has anyone else seen or heard of the vaccine having a date where you potentially need to get another, or a booster, or anything like that.
Thanks

https://www.whec.com/news/expiration-date-on-the-excelsior-vaccine-pass/6060592/

Local news just did a segment about that.

You got to get those boosters every few months, don't ya know.