From the abstract of the paper linked in the article: No change for the UK variant, but lower efficacy for the South African variant (if my understanding of the abstract is correct):

No significant impact on neutralization against the B.1.1.7 variant was detected in either case, however reduced neutralization was measured against the mutations present in B.1.351.

Paper : https://www.biorxiv.org/content/10.1101/2021.01.25.427948v1

This study was done in a laboratory based on blood samples and does not directly equate to a percentage effectiveness. Collecting data on actual effectiveness in the wild, as it were, will require a sufficient number of vaccinated people to come into contact with the variant strains in question, and will therefore take a few months, most likely.

They believe so ("neutralizing titer levels with B.1.351 remain above levels that are expected to be protective"), but this was a blood sample study that can't definitively demonstrate population efficacy.