Hello, returning lurker here too - hiya Flip 
Had my gallstone op almost three weeks ago, only just able to lift DS again now. Has been tough on DP doing solo nights while on deadline so working long days. My DM & DSis had DS during the days and I missed him horribly, but was utterly stoned on painkillers, no way I could care for him.
This is a timely return - our nights have nosedived recently ??
DS has never had a routine due to our illnesses - we've both been in and out of hospital. Just recently (in the last fortnight!) we'd succeeded in getting him down to sleep around 8pm, waking for a dream feed around midnight then he would rarely be up again before 8am. Spoiled, I know. Thought we'd cracked it and really enjoyed having a short time for us in the evenings.
Then the last three nights he's fussed until 10 or 11 pm, then slept until 5 or 6, and has woken a few times through the night. We're both a bit broken. Is this the dreaded 4mth sleep regression (he is 20wks, born 4wks prem in September so 16wks corrected)?
He's in his Snuzpod next to me now, cooing, giggling, being adorable but not sleeping. Gah!