Urgent - Switching from TIER 2 ICT to TIER 2 Dependent

Hi,

My company is planning to sponsor me to travel to UK uner Tier 2 ICT Established staff. The exact sub category of the visa has not been decided but it would wither be long term staff or short term staff. My wife is also working for the same company and she would also be travelling with me in the same category that Tier 2 ICT Established staff (long term staff or short term staff). However she is expecting and her due date is July End, 2014. She is planning to go to maternity leave from July and would not join back to work until November, 2014.

Our questions are the following

1. Can she switch from TIER 2 ICT established staff visa to Tier 2 ICT Dependent visa from within UK(without returning back to India)?
2. If the answer to question no. 1 is yes, then after her leave is over can she switch from TIER 2 ICT dependent to TIER 2 ICT Established staff mode once she is fit to join back? Can she do this from within UK or wouldshe need to travel back to india?

Please let us know.
Thanks and regards,
Sendeep