Sofa may work, depends on how it looks. I guess I will decide when I arrive if I want to pay for a rollway bed or do the sofa.

I spoke to reservations to see what kind of suite I am in and they said it will be an executive suite. I double checked that the notation for the upgrade is for all 3 nights, as each night has a separate confirmation number as I was unsure of my dates when I placed my booking. I decided that it's not worth the money for early check in, as I will be spending my morning touring Singapore at any rate, and for just a shower and to unpack I don't want to splurge.

Any risk of losing my upgrade if I cancel the first night online?

Also do the suites have terraces? Thanks everyone for helping me out!