  HS0705+6700 (also identified as V470 Cam) is a short period (2.3 h) post
common envelope detached eclipsing sdB binary system which exhibits transit
time variations (TTVs) of a cyclical nature. We report a further 25 timings of
light minima and show that our new TTVs support and extend this cyclical
pattern to 1.6 periods. We examine possible causes of the observed TTVs and
confirm that the presence of a third, and possibly a fourth, body could provide
an elegant explanation of these cyclical variations. However other
non-circumbinary mechanisms, e.g. Applegate magnetic dynamo effects, will
remain possible contenders until sufficient data has been accumulated to
demonstrate that the periodicity of the TTVs is time independent.
