vaccines for variants

[JS87]

When do you think they will start making vaccines against the new variants. The companies keep saying that it will only take a matter of weeks to alter the vaccine, yet none of them seem to have started doing it at scale. Surely they should already be scaling up production of vaccines against the new variants (Brazil and SA)?
Presumably they haven't as maybe they would need to go through some sort of trial again and they are concentrating on scaling up vaccine for the original variant.
I just feel like maybe the original variant will be superceeded by the new variants everywhere soon (like the Kent variant has taken over in the UK) and the sooner they start the better.
Personally I'd also be happy to have vaccine against the new variant/ mix of variants without further trials if the vaccine technology has already been proven safe and effective against the original variant.
I'm just wondering what sort of information they are waiting for to make a decision about producing a vaccine against new variants?

They have been testing the current vaccines against the new variants

So far the vaccine has the same effect on the Kent variant. The South African variant does reduce the vaccine effect but it is still higher than the world health organisation recommends

All the vaccines so far even if the efficacy is lowered slightly still work to prevent serious illness or death

Obviously if a variant is found that the vaccines don't work on. Then they will tweak them quickly and add to the roll out. Pfizer reckons that will take them 6 weeks and AZ say 30 days. So all sounds under control.