When I get notified that my Dropbox storage limit is getting close, I move backups over to my hard drive and I make sure that I keep them for a specific period.
I've just received a Dropbox notification to this effect and found that my two Multisite installs - ThinkBiGSites.co.uk and JustThinkBiG.co - have both had all Snapshots deleted after the last Snapshot that was taken on the 19th February. The same has happened with Managed Backups, which were active on bot sites until the last backup.
This is the second time this has happened over the last few months. I didn't report the first occasion because I put it down to a glitch, but this needs to be investigated as to why this has happened.
I'm assuming that it was after an update but I don't know the real reason. What I do know is that I take daily backups and promote that to my clients. If this fails to happen, as is the case here, I'm open to a potential problem if a site does get hacked. It's also quite a nuisance, having to set everything up, all over again.
Please can you investigate why this has happened / is happening and let me know what's being done about it. After all, I need a reliable backup solution, not one that's going to suddenly stop working and delete everything that's been setup.