Could you give more info about the source(disk) and tape jobs schedule? Also what option of new media set creation do you have?
pkelly_sts wrote:Further information: I started with a plan that had a tape-per-week (containing full backup + 6 incrementals) by creating a new media set each saturday. I've changed my mind on how I want to manage tapes and decided that just spanning all available tape space is better (for us) than wasting 1.4Tb/tape each week.
If you create a new media set once a week using incremental source job with synthetic fulls and manually make the oldest tape unprotected it will be rewritten from the beginning, i.e. from .vbk, but since you have 4 weeks of backups on tapes, newer chains on newer media sets will be untouched.