I went to Spain with my 6w old (bag sleeper with colic..) and nearly 2yo, and it was great. In had a planned section, and was feeling pretty great within a week, so totally back to normal by the time we went away.
I've found its definitely easier to travel when they are tiny, than when mobile or a toddler.
That was our second, but I'd have happily done it with our first as well (and we'd been on a couple of overnight stays by that time with our first).
Yes, you may still have lochia - that's what pads are for, it's just like navigating a really long period.
You may be leaving from boobs. Just make sure you pack breast pads.
The bigger issue is that you won't know how the birth will go. A very uncomplicated vaginal birth or a straightforward planned section and you may be fine. Or you could be induced 2 weeks overdue, in labour for 2 days, and have forceps followred by an emergency section, and then an infection. Then you're unlikely to be feeling up to going away a month later. Or more likely, a birth somewhere in between.
More than anything though - a caravan, with your in laws, in November. I wouldn't want to do that without a baby.