Trading Loss this year, page-63

Hey Sojourner, I am quite new to investing and as such this will be my first time accounting for capital gains in my tax return. I am just wondering if you could help clarify some of my queries about this decision or could point me to where I could find the information I seek.

My questions:

1. If I decide to claim my BIG shares as capital losses, do I need to do so before the company publicly is delisted or do I have a chance to see if BIG relists?

2. If I do claim this loss, is the total value of the loss counting to reduce my tax or only a portion of my loss?

Cheers,

LA