I'm currently on the VF VDSL + home phone 80GB plan, which has generally been enough, sometimes overrunning by 5-10GB at the end of the month but at $1 per GB not worth changing to unlimited.

However, with both kids getting tablets around Christmas, relative staying with us and having started to use Netflix recently (as well as existing BBC use) I'm close to blowing my data allowance and it's only a third way through the month.  Previously I've been able to "double my data" for $20, but this is no longer available.  I've also previously been able (not sure if this was VF because I change ISPs every few years) to change plans mid-month and get the extra data allowance immediately.  With the current contract, all I seem able to do is to upgrade from the start of Feb (done) and wait for a large bill to arrive.

Any suggestions?  Is there any way VF will allow me to buy another chunk of data or get an immediate upgrade to unlimited?  I've logged a call with customer service but anecdotes on this forum mean I'm not holding my breath for a helpful response.