SQ's OTT use of the seatbelt sign, and LSS lectures

[SQfanatic]

SQ426 to BOM a couple of days ago - Captain came on with landing announcement and seat belt sign 55 minutes before landing. Crew tried to get everyone to get their seats upright 50 minutes before landing. I don't often refuse to obey instructions on board, but this time I put my foot down and stayed down for another half hour.

I would understand if it might be due to a turbulent landing (i.e. SQ15 I took in 2015 on SWE, pilot did something similar but warned upon landing it would get bumpy and the cabin would be secured early) but if it was not the case, honestly it would irk resting passengers such as myself if we are sleeping.

I thought normally pilots make announcements 30-35 min before landing and seat belt signs typically come 10-15 min before landing.