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We present optical photometric and spectroscopic observations of the02es-like type Ia supernova (SN) 2022ywc. The transient occurred in theoutskirts of an elliptical host galaxy and showed a striking double-peakedlight curve with an early excess feature detected in the ATLAS orange and cyanbands. The early excess is remarkably luminous with an absolute magnitude $\sim-19$, comparable in luminosity to the subsequent radioactively-driven secondpeak. The spectra resemble the hybrid 02es-like SN 2016jhr, that is consideredto be a helium shell detonation candidate. We investigate different physicalmechanisms that could power such a prominent early excess and rule out massivehelium shell detonation, surface $^{56}$Ni distribution and ejecta-companioninteraction. We conclude that SN ejecta interacting with circumstellar material(CSM) is the most viable scenario. Semi-analytical modelling with MOSFiTindicates that SN ejecta interacting with $\sim 0.05\,$M$_{\odot}$ of CSM at adistance of $\sim 10^{14}$ cm can explain the extraordinary light curve. Adouble-degenerate scenario may explain the origin of the CSM, either bytidally-stripped material from the secondary white dwarf, or disk-originatedmatter launched along polar axes following the disruption and accretion of thesecondary white dwarf. A non-spherical CSM configuration could suggest that asmall fraction of 02es-like events viewed along a favourable line of sight maybe expected to display a very conspicuous early excess like SN 2022ywc.

Unprecedented early flux excess in the hybrid 02es-like type Ia supernova 2022ywc indicates interaction with circumstellar material