Edited: In an effort to hopefully calm some nerves over the vaccine validity time-frames, please take note of what the EU has recently said regarding the vaccine and booster.
The EU adopted a rule to make the covid certificate valid for nine months after the completion of the primary vaccination schedule. This rule applies to the original shots and not the booster. The EU has said there is not enough information about the duration of protection from boosters.
Vaccination certificates will be accepted by Member States for a
period of nine months since the administration of the last dose of the
primary vaccination.As of yet, no standard acceptance period will apply to certificates
issued following the administration of booster doses, given that
sufficient data regarding the period of protection is not yet
available.
https://ec.europa.eu/commission/presscorner/detail/en/ip_21_6837
Keep in mind that Europeans also use the vaccine certificates. Once they are past 3 or 6 or 9 months from their boosters, they will be in same boat as us as tourists. With no second booster being offered yet, it’s reasonable to assume that in the future, if a second booster is not offered, the validity of the covid certificates (with the booster) will be extended or no longer used. Otherwise, no one in Europe will be able to dine in or ride the train or whatever else the certificates are used for. The rules will be changing in the future because they will have to. Please be patient and understand the rules in place today will not be the same rules in place months from now.
Sorry for the post 😊, but I hate to see so many people stressing themselves out when their trips are not for several months yet. The rules will be changing.