Comparison of the total number of accepted candidates (y-axis) with the fraction of the comparison sample SNe Ia detected (x-axis). Symbol shapes indicate the typical phase at which objects in the comparison sample were detected: channels where more than 25% were detected prior to phase −10 are marked as early (squares). If instead more than 95% were detected prior to peak light, the channel is defined as suitable for peak classification (circles). Channels not fulfilling either criteria are marked with triangles. Left panel: full channel content. Channels are divided here according to those where transients in galaxies known to host AGNs are cut (black) and channels where these are accepted (gray); cf. Table 3. Right panel: comparison of the total number of accepted candidates (y-axis) with the number of comparison sample SNe Ia found, with only candidates linked to a galaxy with known spectroscopic redshift z <  0.1. All channels reject transients in host galaxies with known AGNs; cf. Table 4. Three channels further discussed in the main text are highlighted (red circles).