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Early JWST observations that targeted so-called double-break sources(attributed to Lyman and Balmer breaks at $z>7$), reported a previously unknownpopulation of very massive, evolved high-redshift galaxies. This surprisingdiscovery led to a flurry of attempts to explain these objects' unexpectedexistence including invoking alternatives to the standard $\Lambda$CDMcosmological paradigm. To test these early results, we adopted the samedouble-break candidate galaxy selection criteria to search for such objects inthe JWST images of the CAnadian NIRISS Unbiased Cluster Survey (CANUCS), andfound a sample of 19 sources over five independent CANUCS fields that cover atotal effective area of $\sim60\,$arcmin$^2$ at $z\sim8$. However, (1) our SEDfits do not yield exceptionally high stellar masses for our candidates, while(2) spectroscopy of five of the candidates shows that while all five are athigh redshifts, their red colours are due to high-EW emission lines instar-forming galaxies rather than Balmer breaks in massive, evolved systems.Additionally, (3) field-to-field variance leads to differences of $\sim 1.5$dex in the maximum stellar masses measured in the different fields, suggestingthat the early single-field JWST observations may have suffered from cosmicvariance and/or sample bias. Finally, (4) we show that the presence of even asingle massive outlier can dominate conclusions from small samples such asthose in early JWST observations. In conclusion, we find that the double-breaksources in CANUCS are not sufficiently massive or numerous to warrantquestioning the standard $\Lambda$CDM paradigm.

$\Lambda$CDM not dead yet: massive high-z Balmer break galaxies are less common than previously reported