  As the sample size of repeating fast radio bursts (FRBs) has grown, an
increasing diversity of phenomenology has emerged. Through long-term
multi-epoch studies of repeating FRBs, it is possible to assess which phenomena
are common to the population and which are unique to individual sources. We
present a multi-epoch monitoring campaign of the repeating FRB source 20180301A
using the ultra-wideband low (UWL) receiver observations with Murriyang, the
Parkes 64-m radio telescope. The observations covered a wide frequency band
spanning approximately 0.7--4 GHz, and yielded the detection of 46 bursts. None
of the repeat bursts displayed radio emission in the range of 1.8--4 GHz, while
the burst emission peaked at 1.1 GHz. We discover evidence for secular trends
in the burst dispersion measure, indicating a decline at a rate of
$-2.7\pm0.2\,{\rm pc\,cm^{-3}\,yr^{-1}}$. We also found significant variation
in the Faraday rotation measure of the bursts across the follow-up period,
including evidence of a sign reversal. While a majority of bursts did not
exhibit any polarization, those that did show a decrease in the linear
polarization fraction as a function of frequency, consistent with spectral
depolarization due to scattering, as observed in other repeating FRB sources.
Surprisingly, no significant variation in the polarization position angles was
found, which is in contrast with earlier measurements reported for the FRB
source. We measure the burst rate and sub-pulse drift rate variation and
compare them with the previous results. These novel observations, along with
the extreme polarization properties observed in other repeating FRBs, suggest
that a sub-sample of FRB progenitors possess highly dynamic magneto-ionic
environments.
