The norm is for each new roll up of your data to replace the last. This does not mean files and folders are discarded, merely that only recent versions are kept because prior versions of most finalised documents are of little interest.

However there may be a need to keep previous versions of certain files, going back for months or years, and in such cases Book Backup does give you the facility to retain, rather than replace, the month end ‘rolled up’ data sets for as long as you wish. If you applied this to our example above, by mid-December you would have all the versions you had created in November and December plus rolled-up versions from the ends of October, September, August and July.

Of course the fewer rolled up versions you keep the smaller your backed up data and the lower the cost.