You would probably say they have a grace period, but unfortunately it only "protects" people born in the country that currently doesn't not exceed the per country limit. People from Philippines, China, etc will get the impact almost immediately. To make this really fair, we need to create extra quota for people born in India, not grabbing quota from other countries. (But I guess this will diminish the chance of this bill getting passed so they choose to hurt others, which from the perspective of people born in India, I totally understand, but I feel sad that I and other people not from India will get hurt inevitably once this bill passes).
[edited for typos]