LO has always been a crap sleeper. Never slept more than 4 hours. Averages 5 or 6 wake ups per night (had a couple of good night's with only 3 wake ups not long ago), comfort boob back to sleep (co sleep from about 11pm. In cot till then).
He's 8 months and in the last week has cut his first 2 teeth, mastered rolling onto front, started sleeping on his front, is walking in his walker, is almost crawling, has started waving. There's probably more too.
This has got to be why he's not going down to bed. And why we're back to waking every hour.