Heading out on the SQ0319 in February and have a few questions

1) Am i flying on a 777-300er or a A380-800 as various sites show both flights. I believe the 777 is more comfortable in Y class than the A380 but the A380 is more quieter.

2) I fly out at of LHR at 18:15 & arrive at SIN the following day at 14:55. Does anyone know what the food & sleep schedule will be for that flight i.e what scheduling do we receive the food. Is it Supper, followed by Breakfast followed by Lunch & also what time will the cabin lights go down so we can hopefully get into Singapore time as quick as possible.

3) Do I require to some sort of jumper / pullover instead of a collared t shirt or short sleeved shirt. Is the cabin cold or hot throughout the flight.

Thanks all in advance

SheepyAFC