Connection time for domestic-international flights at Melbourne

[MEL] Is a 70-minute DOM>>INT connection safe or insane?

So I've got a 70-minute connection in Melbourne this Saturday, flying down from Sydney and connecting through to Singapore and onwards. The connection is around midday.

I'm genuinely curious whether or not it will pan out, given I need to visit the GST refund (just to scan a QR code) and I'd like to make a dash into the lounge in MEL for a quick set of photos.

Has anyone tried pulling this stunt before? Has it worked? Should I go ahead with it or should I start begging the service desk the moment I sniff the slightest whiff of irrops?

It's booked on the same PNR so I'm covered, and I can afford to be at my final destination a day late.

Oh, I should mention it's in J so I should have Express Path to rocket through international security and immigration.

I would just ring them up and get them to bump you to an earlier flight to save the hassle (both yours and theirs) if things go awry. 

I did the same recently. ADL-MEL-HKG. Had a tight one and got them to move to an earlier ADL-MEL flight. They were happy to oblige. 

Ooh. I could do this. In your case, did the agent accept "connection too tight" as a valid reason? Did you need to pay a fee? I'm on a Classic Award in Business and Saturday's SYD-MEL inventory has zeroed out.

Give them a ring and see how you go. 

Will do. I'll report back, probably sometime after sunrise.

Last time I was in this situation I simply got myself moved to an earlier flight upon checkin at the airport. The checkin desk girls have the discretion to do this, so if you show up early they probably will.

So I rang up just now, and I'm told there's only one seat left on the 0600 flight. I'm not comfortable making this flight as the first train from the City doesn't arrive till 0518 and I will need to complete international check-in.

I'll go in early, around 0630, and see what they can do. Should I OLCI before heading out or no?

I'm considering ringing up again to ask if they can force-open inventory on the 0800 flight given that revenue seats are still being sold. D'you think I'd get away with that?

Provided your itinerary has already been ticketed, what I would do is turn up very early to the airport and ask to be moved to an earlier domestic flight. Phone staff make it sound impossible if there's no inventory on earlier flights, plus you'll be up to pay the penalty for changes.

Already ticketed. No inventory apart from one seat on the 0600 flight, which is much too early for me.

The Tourist Refund Scheme closes 60 minutes before your scheduled flight time so if you are definitely wanting to visit this then you'll need more than 70 minutes connection time as it is past security and immigration (even with an express pass).

Close of TRS is T-30, not T-60. Unless that's changed, of course.

If this is the case then if I were the OP I wouldn't worry too much about it. 

Even if you can't get bumped to an earlier flight, which you probably can, 70 minutes seems like plenty of time to make a domestic to international connection at MEL, especially with an express pass and on the same PNR with bags checked through. The terminals directly abut one another, and neither terminal is all that big, so it's really not much of a journey at all. 

I think I'll sit on it and go in extra-early that morning.

Thanks everyone for all the help.