Ensembles crash in CDERebaser.m

Question

In Ensembles, I'm getting a crash at this line in CDERebaser.m in the method "rebaseWithCompletion":

BOOL passedChecks = [revisionManager checkRebasingPrerequisitesForEvents:eventsToMerge error:&error];

The crash is EXC_BAD_ACCESS.

I've had Ensembles working in production on the store for a few months with no issue at all until now. This crash just started randomly occurring. No updates to the app were made.

Any ideas?

** UPDATE **

Stepping through it, it seems to fail in this conditional statement in CDERevisionManager.m:

    if (![self checkContinuityOfStoreModificationEvents:eventsWithBaseline]) {
        methodError = [NSError errorWithDomain:CDEErrorDomain code:CDEErrorCodeDiscontinuousRevisions userInfo:nil];
        result = NO;
        return;
    }