  Development related to PandABox-based fly scans is an important part of the
active work on Mamba, the software framework for beamline experiments at the
High Energy Photon Source (HEPS); presented in this paper is the progress of
our development, and some outlook for advanced fly scans based on knowledge
learned during the process. By treating fly scans as a collaboration between a
few loosely coupled subsystems - motors / mechanics, detectors / data
processing, sequencer devices like PandABox - systematic analyses of issues in
fly scans are conducted. Interesting products of these analyses include a
general-purpose software-based fly-scan mechanism, a general way to design
undulator-monochromator fly scans, a sketch of how to practically implement
online tuning of fly-scan behaviours based on processing of the data acquired,
and many more. Based on the results above, an architectural discussion on
>=10kHz fly scans is given.
