I do not think that is a hard and fast timing on award space release..... I had been watching to book an award flight for Feb'24 and it did not show in SQ website until midnight Central Standard Time (which would be 1 pm Singapore). Fortunately, I was still checking at midnight and was able to snag 2 F awards in Suites.

The 8 am time on day 355 might be good advice generally speaking, but if anyone is looking to capture a highly sought award route, I would keep rechecking the SQ website consistently from the 8 am time target on if nothing initially shows available... persistence pays off.