  We report the discovery of robust spectroscopically confirmed Balmer break
(BB) galaxies and candidates, with secure spectroscopic redshifts $7.1 \le z
\le 9.6$ from publicly available JWST extra-galactic photometric and
spectroscopic surveys. To do so, we used dedicated filters probing the Balmer
break and inspected the objects with NIRSpec spectroscopy. We recover the
previously known objects with strong Balmer breaks and reveal 10-11 new objects
with clear BBs, thus tripling the number of spectroscopically confirmed
galaxies with a BB at z >7. Approximately half of them show a pure BB and no
signs of recent star formation, whereas the other half shows BB and emission
lines, indicating most likely galaxies whose star formation ceased earlier and
has restarted recently. Overall we find that ~10-20% of all galaxies from our
sample show signatures of an evolved stellar population. Furthermore, we find
that the strength of the BB does not strongly depend on the rest-optical
brightness of these sources. In short, our work confirms that photometry alone
has the potential to measure BB strengths and to identify evolved stellar
populations at high redshift and that such objects may be more frequent than
previously thought.
