My info so far:
for the client that we had just purchased domains & mailboxes and started the warming up, we decided to just buy new domains. vary more the names, different times and days, different providers. it'll be a bit more work on the side for Scaledmail and us with giving them the 2fa codes...but it's what we could think of to avoid this issue again
for clients who were already warmed up and about to launch, we decided to carry on. we'll still buy new domains and start warming up, but after a few placement tests and manual emails attempts, we were still landing on inboxes on Google without any issues
Doesn't seem to be a shared IP thing.
Scalmedmail itself made an article kinda saying "ignore this", but they have the incentives to say this of course.
I will ask scaledmail in the future to change their DMARC record (quarantine, with dmarc@scaledmail.com email to an email from us so the DNS doesn't read scaledmail)
