[mothered]

Should I order it to a similar address? i.e. next door house, same street, same town, etc?

Any address that's not associated to yours.

Should I order them to arrive on the same day? e.g. amazon day delivery
Should I order both phones at the exact same time?

The arrival date Is not relevant.

Each Item can be ordered on separate days (the method has proven to work as such) but to play It safe, order each one on the same day.

After the iphone comes, I'll collect the other non-iphone then take pictures to show that It's the correct shipping but wrong item. Should I just call amazon after this? and tell them that the wrong phone has come?

Forget about taking photos etc. It's unnecessarily complicating matters.

All you're concerned with, Is that you've received an Incorrect Item to what was originally ordered - which Is exactly what you'll tell the representative. The next course of action will be based on their reply.

Do you know roughly how long amazon takes to complete their investigation for this type of problem?

Impossible to generalize.

Every claim Is assessed on a case-by-case basis.