My waters broke 10 days before my ELCS date (also for psychological reasons), so I was glad I'd had this conversation with my consultant and MW!
Their advice was - go to hospital as SOON as you think something may be happening. By all means ring in advance, but if the MW on the end of the phone (who may not know your circumstances, and be busy) tries to make you wait, ignore her and just go straight in.
This is just because very rarely, labour can progress very fast, and you want to make sure you get your CS before things are too advanced.
You can ask for it to be written on your notes that you have no desire for a VBAC, and that you want this to be respected. If you have an ELCS agreed, there is no reason at all why you shouldn't have one. You can say you are worried you will get people who will try and persuade you to do otherwise under these circumstances - that having got your ELCS agreed, you don't want to have to any conversations about it which involve going over distressing territory again with various different MWs.
I asked for the reason for my CS to be put in my notes, and for it to be written that if I went into labour early, there was to be no attempt at VB. When this happened, everytime someone said 'why are you having a CS?' or 'why do you want one?' I could just say, please read my notes.
All that happens if you go into labour is that they do your CS earlier. Technically it counts as an EMCS, but there's not the same 'emergency', IYSWIM.
My waters broke, and apparently I was contracting although I couldn't feel anything. That was late on Weds night - I went in the same night, and was told things weren't progressing fast, so I could either stay overnight and have my CS the next day, or go home and come in in the morning.
I did the latter, to get a sleep in my own bed - then came in at 8 in the morning, should have been in theatre by 10, but it ended up being nearer 6. This was just because there were a lot of EMCS's and instrumental deliveries needing the theatre, and obviously they take precedence. It was a bit of a long wait, but basically fine. They kept assessing me to make sure labour wasn't progressing, and they didn't need to bump me up the list.
I think your question is sensible, but if you can have a quick conversation with your consultant/MW, and ask them to write in your notes that you do not want to be encouraged to VBAC, that's a positive action and should hopefully bring you some peace of mind.
Good luck. My CS was great btw, a very positive experience with a very quick and easy recovery (and a very happily BF-ed baby).