Hopping => you probably want to be in T1 (QR/QF/BA lounges)- good luck with the inter terminal transfers!

Checkin @ Jewel (&straight to T1) would be ideal but seems that CX isn’t on the Jewel checkin list.

https://www.cathaypacific.com/cx/en_...i-airport.html says 3h before, and this is pre covid, I had no issues getting my boarding passes significantly earlier in the day- perhaps give it a shot if you don’t have anything else to do!

btw, dated, but useful:

https://onemileatatime.com/singapore...-access-rules/