Physics is not going to be marked online, so your actual papers are going to be marked, not a scanned version.
In the past:
Anything on the page is marked, even if after the last line of writing. If you need more space, then extra booklets can be requested and used
In longer mark questions there is logical and coherent as part of the marking scheme, which if you place bits randomly round the paper, you aren't going to achieve.
Board of Studies has always stated the space provided is enough to answer the question to the depth required. They are implying that from 2010 and after they may be trying to enforce it. I don't know how or if they will be successful but when students have written 6-8 pages for a 4 mark question and received 0, I can understand why they are doing this.