I don't think it'll ever happen. Even if Charles or William really, really, really wanted to remove Harry (or Andrew) from the line they have to think of the wider consequences of such a decision.
Once you start meddling with the line like that, or removing titles because someone steps out of line, then you highlight that it can be done. Even suggest there are times when it should be done
Think back to when Diana died - Charles was one of the most unpopular men in the world. All the calls for William to be put his place etc. imagine the amplification of that if there was a precedent of removing people?
As much as Harry, and Andrew, are an issue for them they know that the next person the media are questioning could be them. Or George, or Charlotte or Louis.
Starting to meddle in things like the line of succession, and removing the automatic right of it, is the start of the end for them all and they won't risk that for themselves or the Wales children.