3 mugs all looking the same, 1078, 1329, 1379

In the gallery the items for 1078, 1329 and 1379 look identical.
Are these mis-readings of blotchy marks or three separate items?

I have a castware mug, brown glaze, 102mm H x 74 OD at lip,
matching all three, clearly numbered 1078.
(Or is it 1028? )

Great work Jeremy as I didn't have any records to verify the so called 1379 when sid posted it. The records show that the 1379 is a small 8 sided Flower Pot, so it's definitely has to be a wrongly interpreted number and I will remove it from the Gallery.
The 1078 is correct - first made 4.3.70
and the 1329 entry is "New 1078 with thicker handle" first made Sept 80