Hi all!

I'm currently traveling around Europe using my UA miles and having a great time. Through the numerous changes I've made to my itinerary, I overspent on miles and now have a negative balance showing in my account. As I am mid-way through an itinerary, I thought it best to own up and transfer/buy miles to get back to 0, which I have now done. My question is whether my upcoming flights are safe, or if in the interim "48 hours" that it can take for miles to post, the flights could be cancelled. I have four segments of an existing itinerary that I am flying tonight and then Friday, plus another reservation on Monday that is two segments. I've heard horror stories of people's flights being cancelled due to a negative balance, so I just want to make sure I don't get stranded somewhere in Europe!

Is it worth calling anyone at United to let them know I have tried to fix things, or is that more likely to confuse?

Thanks for any and all advice.

P.S. I thought about downgrading some of my segments to claw back miles but the system won't let me initiate a move from I to X as it wants to start at a zero balance.