P{GawB}biomb1-GAL4 is inserted 14,264bp downstream of the bi transcription start site.
Imaginal disc expression resembles and is broader than that of bi, but the embryonic pattern is different. Embryonic and imaginal expression is the same as that of ScerGAL4bi-omb3-GAL4. See Figure 1 in FBrf0152374 for images of expression patterns.