  The discovery and timing follow-up of millisecond pulsars (MSPs) are
necessary not just for their usefulness in Pulsar Timing Arrays (PTAs) but also
for investigating their own intriguing properties. In this work, we provide the
findings of the decade-long timing of the four MSPs discovered by the Giant
Metre-wave Radio Telescope (GMRT), including their timing precision, model
parameters, and newly detected proper motions. We compare the timing results
for these MSPs before and after the GMRT upgrade in 2017, characterise the
improvement in timing precision due to the bandwidth upgrade. We discuss the
suitability of these four GMRT MSPs as well as the usefulness of their
decade-long timing data for the PTA {experiments. It may aid} in the global
effort to improve the signal-to-noise (S/N) of recently detected signature of
gravitational waves in cross-correlation statistics of residuals of MSPs.
