six on/six off -don't plan on it...the majority of trips are three day trips and will be separated on your roster by two clear days - however you may may be able to "back to back" two 3 day trips , either as part of the allocation process or by swopping with your colleagues. Sadly you may have to back to back in order to hit the monthly hours target .
Shuttling/commuting - lots of people do it from all over the EU and further afield.
Standby duty - You need to understand the terminology here. You will do a Reserve month very roughly once every year / 18 months (initially). Whilst on Reserve you are required to be contactable by the Company every evening for allocation of a duty the following day. Also within that month you will do several days of "Home Standby" where you have to be available for report within 2 hours.