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$JWST$'s first glimpse of the $z>10$ Universe has yielded a surprisingabundance of luminous galaxy candidates. Here we present the most extreme ofthese systems: CEERS-1749. Based on $0.6-5\mu$m photometry, this strikinglyluminous ($\approx$26 mag) galaxy appears to lie at $z\approx17$. This wouldmake it an $M_{\rm{UV}}\approx-22$,$M_{\rm{\star}}\approx5\times10^{9}M_{\rm{\odot}}$ system that formed a mere$\sim220$ Myrs after the Big Bang. The implied number density of this galaxyand its analogues challenges virtually every early galaxy evolution model thatassumes $\Lambda$CDM cosmology. However, there is strong environmental evidencesupporting a secondary redshift solution of $z\approx5$: all three of thegalaxy's nearest neighbors at $<2.5$" have photometric redshifts of$z\approx5$. Further, we show that CEERS-1749 may lie in a $z\approx5$protocluster that is $\gtrsim5\times$ overdense compared to the field. Intenseline emission at $z\approx5$ from a quiescent galaxy harboring ionized gas, orfrom a dusty starburst, may provide satisfactory explanations for CEERS-1749'sphotometry. The emission lines at $z\approx5$ conspire to boost the $>2\mu$mphotometry, producing an apparent blue slope as well as a strong break in theSED. Such a perfectly disguised contaminant is possible only in a narrowredshift window ($\Delta z\lesssim0.1$), implying that the permitted volume forsuch interlopers may not be a major concern for $z>10$ searches, particularlywhen medium-bands are deployed. If CEERS-1749 is confirmed to lie at$z\approx5$, it will be the highest-redshift quiescent galaxy, or one of thelowest mass dusty galaxies of the early Universe detected to-date. Bothredshift solutions of this intriguing galaxy hold the potential to challengeexisting models of early galaxy evolution, making spectroscopic follow-up ofthis source critical.

Schrodinger's Galaxy Candidate: Puzzlingly Luminous at $z\approx17$, or Dusty/Quenched at $z\approx5$?