What should I do if I miss my cat’s vaccine due date? - Freeport Veterinary Hospital
What should I do if I miss my cat’s vaccine due date? - Summer Creek Animal Clinic
Stuff happens, and sometimes the vaccine dates are off. The best thing to do is get in as quickly as possible so that the veterinarian can discuss lifestyle with you and make the appropriate recommendations on which vaccines need to be continued and how often. If you've missed the initial booster series—for example, if a leukemia vaccine was given, and then you miss the booster a month later, if it's beyond six weeks from the initial vaccine, it does have to be started over. And so you have to do the initial series of two vaccines a month apart. The immune system must get that initial boost to provide the full immunity that we want.
What should I do if I miss my cat’s vaccine due date? - Animal Hospital of Statesville
I guess the answer would be to get in ASAP and get it done. In some cases, like how I mentioned before, if you go too long between certain intervals depending on their age or what vaccine it is, you may have to restart the series. You may have to start back over and give an extra booster. So the timing is essential, and you don't want them to have a lapse in it. Get them updated as soon as you can.