Weird exposure report

[bwgref]

For sequence ID 90601035001

obs = info.Observation(path=here, seqid='90601035001')
obs.exposure_report()

returns:

Exposure for FPMA, mode 01 is: 7.923 ks
Exposure for FPMA, mode 05 is: 8.721 ks
Exposure for FPMA, mode 06 is: 0.798 ks

Exposure for FPMB, mode 01 is: 7.843 ks
Exposure for FPMB, mode 06 is: 0.7891 ks

...even though there is no Mode 05 data (that's the calibration source being deployed) and no Mode 05 event file.