Quasars are the supermassive black holes at the centres of early galaxies. Scientists have unlocked their secrets to use them as ‘clocks’ to measure time near the beginning of the universe.
In the early universe time ran much slower compared to the current period. This was already known, but scientists have pushed this back to a billion years after the big bang, when time ran 5x slower compared to now.
I don't think it would change the age of the universe as measured from the inside since with slower time a year also ends up being longer. From an outside perspective it would be older though.