When you get a load error, rollback or ignore will never help. You need to have an existing game context for rollback to roll back to, and you don't have one at that point if you just started up Renpy. You can't ignore the error because there is no game context for it to ignore and try to carry on.
Yes it IS possible is some circumstances, that is why I mention that it is a possibility to try and doesn't hurt to see if it works or not. It is also why I gave several options to try besides just this.
...
Renpy label statements are one of the "hints" that allow Renpy to know when to drop a new context point where it can pick up from (saves don't just pickle all of the variables). That can get screwed up if the dev doesn't use labels much, but it's rare that more than a handfull of saves will get borked that way. That's also the reason why some devs throw in labels with names like "xxx_context" which are otherwise not directly called or jumped to from elsewhere.
HOLY SHIT thank you for educating me on all this, I'm so new to Ren'Py and you just took my Renny virginity!
BTW, I will tell you EXACTLY why a few people are having the issues they are having with this update.
Vinyard had tabbed over the labels one level to the right in the 0.45 releases for Day 05 and changed them back to their proper positions in this release and due to the nature of Ren'Py it's fine for most but breaks saves for others. Which is why I gave all those options to try as one of them might work for some but not others before the need of having to Start A New Game and use the
ctrl
key to jump through the dialogue to get to where you need to be.
As for you complaining about him needing to put a banner in the OP Start A New Game when he finally added in game variables, Vinyard is still new to coding in Ren'Py and he is far from the only dev needing users to start over again. It happens more then you know apparently.
Either way good luck on trying to get help in the future as anyone who normally helps is just going to ignore you now due to how you are handing this situation.