delta failure urgent

Hi frnds,

we have a delta monthly load to a cube from six source systems( All R3) schedulled by a

infopackage group, Now the problem is .... except one infopackage all the other five the

delta load has failed 4 months back , update type is only PSA ,update subsequently in data target

now i have to reload the cube from the 5 Source systems with all the data (delta) for the last 4 months ,

i have planned to delete the failed request from the PSA ,

Initialize delta without data transfer

and schedule the infopackage ..

I would like to know ............

is there a better way of doing this?

is there anything mandary to perform before this?

Thanks form any of your sugesstions,

SS