The initial success rate percentages such as 95% etc, will almost certainly change. For example, the B1.351 (South Africa)variant is able to completely evade the vaccine. Therefore, if (probably when) this variant begins to spread in the population the percentages will change with it. We will need a new vaccine using the spike protein for that variant in order to be immune.
That's not true. It's resistant to the neutralizing antibodies, which means it takes more to subdue it. In Moderna's case, they said it's about a sixfold reduction in neutralizing antibody effectiveness, but they also said their vaccine produces so many antibodies that it's still effective even under those conditions.
We will need a new vaccine using the spike protein for that variant in order to be immune.
A booster to ensure full effectiveness has already been produced, tested, packaged, and shipped. They're using it in South Africa right now. One of the benefits of the mRNA platform is you don't need to culture ("grow") anything. You simply print out your mRNA strands, enclose them in lipid shells, and you're done. Instead of taking months or years to make minor changes, it can be done in days and tested in weeks.
https://www.nbcnews.com/science/science-news/moderna-test-booster-shot-targets-south-african-variant-rcna310
Also worth noting that the resistance to neutralizing antibodies is not specific to the vaccines. If you got the April 2020 variant of COVID-19, and if you had a mild or asymptomatic case, you’re almost certainly able to get either the South Africa or the Brazil variants and they can result in a severe case.
This is why it’s important to get vaccinated even if you had a mild case of COVID-19 previously. Having that mild case provides little help against some of the known variants. The vaccines provide significant protection.
On the bright side, Kung Flu has defeated the old flu in a 3rd round knockout so that you'll still only have to take one shot. /s That is if widespread vaccinations in a pandemic don't help produce too many variants too quickly.
There is no evidence any variant avoids the vaccine to date