How did they not know this before?
Well it could be that after given details of some of the issues involved in the defense they discovered something that they were previously unaware or an entanglement they didn't previously know about.
I have learned that Digenova’s well-known connection to the FBI informant on U1 may not be behind the soc-called conflict. It may be because of his (and wife’s) representation of Sam Clovis and perhaps other members of Trump’s team, which hasn’t attracted a lot of attention.