One worry I have is that once I have submitted my thesis, is how long it is going to take to organise the Viva. I have already received some indication that they might like to keep me on after the PhD, but I haven't decided yet what I want to do. If I decide to get a job somewhere else then I'm concerned they might have little motivation to get a Viva organised - any thoughts or experience on this? UK uni with an EPSRC sponsorship.

In my Uni, the arrangements for the viva are made BEFORE submission of the thesis i.e the examining panel are appointed. The exact day may not be finalised until after submission (but it is sometimes arranged before, based on the student's intended submission date).

It typically takes 1-3 months between submission and viva, but I have heard of as much as 12 months occasionally.

I think it's perfectly natural to say to your dept that you have not decided what to do after the PhD. It shouldn't make a difference.

I would have a polite chat with your dept's head, if your supervisor cannot help.

The timing usually depends on having all examiners, chair and sup available at the same time, which is quite difficult !

At my uni you had to sign an "intention to submit" form, before the thesis was handed in. This had to be at least 3 months before the submission was made (although I can't imagine they'd refuse a thesis if a form was sent in less than 3 months prior). You'd have to state who the external was going to be on the form.

As for time between submission and viva, the uni stipulated that the student shouldn't wait for more than 3 months unless in exceptional circs (someone once waithed about 7 due to her examiner being ill)

The onus should nto be entirely on you to arrange a viva - nor should whatever you're doing work wise affect how the uni/department/supervisor organises it. As UFO says, the main issue is usually getting people in one place at the same time!

another point - it's VERY unlikely a uni drag their heels about arranging a viva anyway - it's in their best interests to get students completing as soon as possible so they can include the results on their RAE returns.