Revelation – ‘coffee’ questions

This post is effectively my Post It note of questions to follow up from my weekly Bible study on Revelation at Central Focus.

The idea being that I can do a survey of commentaries to see the different viewpoints on these verses and then add them here.

From Revelation 6-8:6

Horseman 3 – more deatils on whether it is a random affliction of food, or purposeful restraint by the LORD.

Horseman 4 – is it that the horsemen combined have authority over a quarter of the earth, or that individually they each have a quarter of the earth (i.e the whole earth is under the effects of the horsemen). Does the comma mislead?

What is the justification for the shift in time frame from seals 1-4 to seals 5-6? The Lamb is slain, hence must be post Resurrection, but there is a sense in which it is entirely outside time.