Craigybagel will be able to confirm, but I am sure that not every train stops at Craven Arms or Church Stretton. I know that all stop at Ludlow, Leominster and Hereford.
I am afraid not.
Departures from Shrewsbury towards Newport:
0532 all stations
0610 all stations
0647 all stations
0718 Ludlow, Leominster, Hereford, Abergavenny, Pontypool & New Inn, Cwmbran
0744 Church Stretton, Craven Arms, Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
0810 Hereford
0840 Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
0914 Church Stretton, Craven Arms, Ludlow, Hereford, Abergavenny, Pontypool & New Inn, Cwmbran
0940 Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1024 non-stop
1039 Church Stretton, Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1116 Craven Arms, Ludlow, Hereford, Abergavenny, Pontypool & New Inn, Cwmbran
1139 Church Stretton, Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1239 Ludlow, Leominster, Hereford, Abergavenny, Pontypool & New Inn, Cwmbran
1315 Church Stretton, Craven Arms, Ludlow, Hereford, Abergavenny
1340 Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1450 all stations
1515 Church Stretton, Craven Arms, Ludlow, Hereford, Abergavenny, Pontypool & New Inn, Cwmbran
1540 Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1650 all stations
1716 Church Stretton, Craven Arms, Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1740 Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
1850 all stations
1925 Church Stretton, Craven Arms, Ludlow, Hereford, Abergavenny, Cwmbran
1956 all stations
2050 Church Stretton, Craven Arms, Ludlow, Leominster, Hereford, Abergavenny, Cwmbran
2209 all stations
2308 all stations
That is quite some variety! A pattern is... elusive. The minutes past the hour are also very unmemorable indeed.