1 - in theory yes.

You don't want to be bumping up against that line - usually that indicate you've chosen the wrong activity level - too low.
Certain workout schedules cause that to happen too - like 3 big days could burn more than the difference between deficit and BMR on those days (say 1000 for you), and so you reduce the deficit as instructed (eating 206 more those days). But then the other 4 days you are literally eating over TDEE for rest days - so weight loss would be a crawl or actually maintenance.

There are obviously infinite levels, the rough 5 are given for convenience sake. You create infinite by adding on 100-200 calories, or going for average between levels.

And the rough 5 discuss exercise only - nothing about daily life.
Would mail-carrier doing your weekly workout select same level as desk-jockey doing it?
Is person with kids more active in evening/weekend than those without?

So confirm you add a level if kids keep you more active in evenings/weekends than bump on a log outside of exercise, or if work is more than desk job/commute for 45 hrs weekly.

2 - That's why you adjust later based on actual results.

Well, suggest you actually do the math, only a minor deficit with few big workout days cause that to happen of eating over that days literal TDEE.

And actually, there is a benefit to eating at maintenance on regular basis - it's why the 5:2 diet works so well, where 2 days are 25% of average TDEE, and 5 days at TDEE. Body keeps hormonal balance very easily.

So your numbers for example. If truly Sedentary on non-exercise days
BMR 1442 x 1.25 sedentary = 1803 on those days.
1803 + 560 = 2363 on workout days.

Average TDEE by chart = 2236 (so yes, you are below this level if truly sedentary outside exercise, since exercise TDEE is only a tad more)
Average eating level = 1900

So yes, on non-exercise sedentary days you'd be eating 100 more than literal TDEE.
On exercise days you'd be eating 463 deficit.
But that's if the body stopped what it was doing at midnight - which it doesn't.

So your idea is valid - but in that case - just use MFP the way it was designed.
Set activity level to sedentary if this is honest.
Set weight loss goal amount to 1/2 lb weekly or 250 cal deficit. (so little to lose, 15% deficit isn't really reasonable)

Your eating goal on non-exercise days should be about 1803 - 250 = 1553
Which is slightly more than 10% deficit.

On exercise days when you log those workouts your goal will be 1553 + max 560 = 2113
Which is slightly less than 10% deficit.

So average deficit for the week will be about 10%.
And you could always slide some calories from workout day to next day during the recovery to allow you to eat more when the body will be able to use it.