add manual " Activity Sleep "

Manual activating sleep mode enables sleep tracking by the watch. Depending on what happens after sleep mode activation the watch starts sleep tracking. I have set my sleep plan outside my bed time so that it has no effect on my manual start of sleep mode: 1:30 AM - 10:30 AM

and this works fine. To start sleep mode I use a short cut "Light"+"Back" .... 

sure " manual activation sleep mode " works

BUT issues are this
- this is nowhere described that scheduling is just auto settings , and in other time I have to use manual activation means NAP or sleep when I have sleep outside of that scheduling
- if I want automatic all the time and has set it to 00.00-23.59 metrics was completely wrong and tell me that I was sleep almost all day
- also automatic is not correct - like today or others days - it show for example 02.33-11.53 -9:h.20:min " but show only 8:h.50:min - means show -0.5:h or -1:h less

this is why I suggest tracking sleep like all other activity - means have app activity " Sleep " and when I go I go " and metrics will be precices

"Manual activating sleep mode enables sleep tracking by the watch."

This is not correct. Sleep tracking will take place regardless of the setting Sleep Mode.
"Sleep mode" should in my opinion be called "Do not disturb" Mode as is has nothing to do with sleep tracking.
It should also be possible to disable this "Sleep Mode" as it doesn't apply to some people  (an example are shift workers).

Maby things will change when "Nap" functionality from the new Venu is ported over, but this is currently the status.

It is indeed not possible to manually start sleep tracking. It is possible to edit your sleep on Garmin Connect if this helps.

Here som info about sleep tracking from Garmin:

https://support.garmin.com/en-US/?faq=mBRMf4ks7XAQ03qtsbI8J6 

That's correct this info is about sleep tracking, ok it's called Advaced Sleep Monitoring.

As stated nothing to do with "Sleep Mode".

See: https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-7-series/283470/dear-garmin-please-read-in-regards-to-sleep-mode-on-fenix-7

That means, if I don't care about DND and red light shift, I have not to take care about sleep mode,  the watch recognizes my sleep always automatic, also sleep plan settings are not important ...

My personal experience is: manual activation/deactivation of sleep mode gives me the best results for sleep tracking!

That's correct. I've had my sleep tracked during the day while not in Sleep Mode.

To be fair Garmin says that setting your Sleep and Wake times correctly will ASSIST sleep detection, as per your personal experience.
But it literally states in your link that it is a Do Not Disturb Mode !

It will be interesting to see how it will all hold up with the coming Nap detection.

> Sleep tracking will take place regardless of the setting Sleep Mode.

not for me - I sleeping many times through day - means day default window @06-22 and nothing

> "Nap" functionality from the new Venu is ported

I expected that basics have the last version of watch

> not possible to manually start sleep tracking

for me work every time " manually switch " menu " sleep mode : on "

> watch recognizes my sleep always automatic

yes in scheduled windows

> manual activation/deactivation of sleep mode gives me the best results for sleep tracking!

agree - but still there is 30-60 minutes deviation

> To start sleep mode I use a short cut "Light"+"Back"

thx - I didn't notice that shortcut option " Sleep Mode " it's helpful