  Standard models of structure formation allow us to predict the cosmic
timescales relevant for the onset of star formation and the assembly history of
galaxies at high redshifts ($z > 10$). The strength of the Balmer break
represents a well-known diagnostic of the age and star formation history of
galaxies, which enables us to compare observations with contemporary
simulations - thus shedding light on the predictive power of our current models
of star formation in the early universe. Here, we measure the Balmer break
strength for 23 spectroscopically confirmed galaxies at redshifts $6 \lesssim z
\lesssim 12$ using public JWST NIRSpec data from the cycle 1 GO 1433 and GO
2282 programs (PI Coe), as well as public spectroscopic data from the JWST Deep
Extragalactic Survey (JADES). We find that the range of observed Balmer break
strengths agree well with that of current simulations given our measurement
uncertainties. No cases of anomalously strong Balmer breaks are detected, and
therefore no severe departures from the predictions of contemporary models of
star formation. However, there are indications that the number of outliers in
the observed distribution, both in direction of strong and weak Balmer breaks,
is higher than that predicted by simulations.
