  We report the radio and high-energy properties of a new outburst from the
radio-loud magnetar 1E 1547.0$-$5408. Following the detection of a short burst
from the source with Swift-BAT on 2022 April 7, observations by NICER detected
an increased flux peaking at $(6.0 \pm 0.4) \times 10^{-11}$ erg s$^{-1}$
cm$^{-2}$ in the soft X-ray band, falling to the baseline level of
$1.7\times10^{-11}$ erg s$^{-1}$ cm$^{-2}$ over a 17-day period. Joint
spectroscopic measurements by NICER and NuSTAR indicated no change in the hard
non-thermal tail despite the prominent increase in soft X-rays. Observations at
radio wavelengths with Murriyang, the 64-m Parkes radio telescope, revealed
that the persistent radio emission from the magnetar disappeared at least 22
days prior to the initial Swift-BAT detection and was re-detected two weeks
later. Such behavior is unprecedented in a radio-loud magnetar, and may point
to an unnoticed slow rise in the high-energy activity prior to the detected
short-bursts. Finally, our combined radio and X-ray timing revealed the
outburst coincided with a spin-up glitch, where the spin-frequency and
spin-down rate increased by $0.2 \pm 0.1$ $\mu$Hz and $(-2.4 \pm 0.1) \times
10^{-12}$ s$^{-2}$ respectively. A linear increase in spin-down rate of $(-2.0
\pm 0.1) \times 10^{-19}$ s$^{-3}$ was also observed over 147 d of
post-outburst timing. Our results suggest that the outburst may have been
associated with a reconfiguration of the quasi-polar field lines, likely
signalling a changing twist, accompanied by spatially broader heating of the
surface and a brief quenching of the radio signal, yet without any measurable
impact on the hard X-ray properties.
