Starlink or What?

Sky photos from 2020-05-20 to 2020-05-21 at around midnight Gloucestershire UK.

Note the solid trails are faulty camera pixels , the dashed lines are satellites. Not quite so impressive knowing this! 

The first pair are made using the a set of 405 photos stacked using deepsky stacker. The exposure was 0.5 seconds for each with a gap of approx. 2 seconds using f2 50mm lens on m2/3 body.

The first picture uses an averaging stacking to get rid of noise and is the usual mode of stacking.

The second picture uses a maximum stacking algorithm keeping the high intensity pixels for each frame. 

The second picture shows trails (obviously). from slow moving objects and dashed lines from fast movement objects. Note that stacking retains the position of stars in each stacked picture any object not in the same rotation of the earth as the stars will form lines.

the third and fourth pictures are at an exposure per frame of  0.625 seconds with the same camera with aperture set to f1.4. Approximately 1100 frames are stacked:

The third picture uses an averaging stacking to get rid of noise and is the usual mode of stacking.

The fourth picture uses a maximum stacking algorithm keeping the high intensity pixels for each frame

The questions

Are the trails a feature of the stacking? answer the solid trails are faulty pixels the dashed lines are satellites

Why are some satellites moving much faster than others - not starlink - planes?

- some "planes" show up as a cluster of red green white light in one frame only

On the 4th photo why are some satellites "jiggling" Top right of 4th photo. Other stars in same location show no strange movements. Tripod was steady on windless night.

Central coloured spots appear only once on 2nd picture and not at all on first - a plane?

If a plane and this capture shows no motion blur in 0.5sec why does it only appear once in the 200 second capture - in does not appear in the average.

Another splurge of dots from 4th picture (centre) that only appears once - A plane? Note jumbled trail where others are as expected!

Taken 2020-05-29 at 02:17 start 1.6 sec exp f1.4 50mm m4/3 camera body  ~400 pictures averaged Stars Named.

Taken 2020-05-29 at 02:17 start 1.6 sec exp f1.4 50mm m4/3 camera body  ~400 pictures  stacked (as previous) with max intensity retained

Taken 2020-05-29 at 02:23 start 1.6 sec exp f1.4 50mm m4/3 camera body  ~200 pictures stacked retaining max intensity