Unless your 1yr old is very small for his age, he won’t fit in a bassinet. Most airlines have an age and length restriction. We tried getting a bassinet for our son at 13 months (different airline) and they refused. You might be able to still get the bulkhead seats but from what I understand, you could be moved to accommodate another family that needs a bassinet for their infant. We’ve travelled for years with babies and toddlers since they were as young as 6 weeks old, always in economy. Once they were too big for bassinet we booked a seat for them and strapped them into a car seat on the plane. It was perfect because they slept beautifully and didn’t need to be held, even when awake. Thinking back on those toddler travel days brings back memories of endless walks up and down the aisles trying to tire out my little one 😩 it’s a lot more enjoyable now that they’re 11, 9 and 6! Anyhoo, enjoy! 😅

edit: here’s what I found on SIA website (quite a generous size, your 1yr old might just fit) 👍🏻:

BassinetsBassinet seats in Premium Economy and Economy Class are reserved for passengers with infants, on a first-come-first-served basis. Each bassinet measures at 768mm (L) x 298mm (W) x 158mm (H), and can support a maximum weight of 14kg.