Sounded to me like they already get 8 hours generally and it pushes up to 10-11.
That said, it’s important to realize that not everyone needs 8 hours of sleep. Some people are blessed to only need 6, some people are cursed to need 10 or 11 hours. Some people have extreme generic quirks that can go from only needing 4 to needing more than 12 (of course you should talk to a doctor if that’s you). 8 is definitely by far the most common, but it’s not a hard rule.
His post said he sets the alarm for 6-7 hours. And I’d agree with this reply to just plan more sleep initially, and (if you can) skip the alarm. Why? I have had the same experience as him with resuming dreams, and know that the “cure” for me (and just generally feeling more awake for the rest of the day) is consistently about 8h15m of sleep. That’s my number, from estimating the average over some years and mostly avoiding alarm clocks, and yours is probably different. I believe I happen to need more than average. Sometimes changing time zones by 4-5 hours can help me reset the rhythm, as does planning my sleep timing based around when I want to wake, rather than my natural habitation as a night owl.
That said, it’s important to realize that not everyone needs 8 hours of sleep. Some people are blessed to only need 6, some people are cursed to need 10 or 11 hours. Some people have extreme generic quirks that can go from only needing 4 to needing more than 12 (of course you should talk to a doctor if that’s you). 8 is definitely by far the most common, but it’s not a hard rule.