"before the bb", the answer is simple. There were stars older than the BB event
This problem with dating the age of the universe and finding interesting objects dated older than the universe, has been around a long time now. IN SEARCH OF ANCIENT SUNS, https://skyandtelescope.org/astronomy-news/in-search-of-ancient-suns/
My observation. The age of the universe can vary based upon different input parameters like for H0 using the cosmology calculators, https://ned.ipac.caltech.edu/help/cosmology_calc.html
, and, https://www.kempner.net/cosmic.php
. A good example is the kempner.net calculator. Using H0 = 70 km/s/Mpc, the age of the universe is “age of the Universe at z = 13.2451 Gyr” when z = 0 and H0 = 70 km/s/Mpc. Thus some stars can still be dated older than the universe beginning using BB cosmology calculators. This was a problem when H0 = 500 km/s/Mpc in the early days of redshift surveys with the universe age near 2 billion years old. Using cosmology calculator I, H0 = 70 km/s/Mpc and z = 0, the universe age is "It is now 13.642 Gyr since the Big Bang. The age at redshift z was 13.642 Gyr." Using cosmology calculator II with H0 = 70 km/s/Mpc z =0, universe age is "Age of the universe: 13.4112 Gyr, which is 100% of the age of the universe today. Lookback time: 0 Gyr." The Hubble time for age of the universe in the expanding universe model for the BB is very sensitive to input parameter changes. The list of 5 very old stars in the S&T report is also a good example of the 2nd Law operating in the universe, entropy and decay.
So my answer *before the bb*, old stars and globular clusters dated older than the universe