Yes it is fine to eat your last meal at 6:55, it’s also possible to eat for example one hour earlier but then it would be a 17/9 fast.
Personally for me it easiest to eat my last meal 4 hours before sleeping, then I don’t go to bed hungry and after I wake up I only have 4 hours more to go before my first meal.
It doesn’t matter too much really. If you have your last meal at 7, it’s still pretty much 16:8. When I first learned about IF, that’s what I thought you were supposed to do for 16:8 and I still got all the same benefits. You could call it 15:9 fast if you want though. Just make sure you’re consistent is the main thing.
Currently I’m doing 18:6, but it’s really more like 19:5, as I have been having 1 meal at 12pm then my last meal at 5pm, no snacking. But once I lose some weight I may snack again a little bit occasionally and keep that window open until 6pm.