What was he doing before? I have found her total sleep has gone up a bit (which I think is pretty common)
I agree with this although often have seen the night length being only nap plus night equals new night for a little while and then the night lengthen.
and example is my DS who dropped his nap a few months younger:
2hr nap + 9hr night (yes it went as short as that but he couldn't cope without his long nap!) = 11hr sleep in 24hr
no nap + 11hr night = 11hr sleep in 24hr
but then he settled into it and over some time it lengthened to 12hr night - so yes it became more sleep in 24hrs than he was previously on.
And he stayed at 12hrs for 2+ years (bliss!)