The "do not distribute" slide that is floating around has been published by The Register:
https://regmedia.co.uk/2018/01/09/ibm_do_not_distribute.jpg
On the left-hand side are the current positions of the employees, referred to as "sources of release", and on the right-hand side are areas where IBM anticipates them moving to this calendar year, the "uses of release".
Starting with the (a) column on the right-hand side, IBM stated that 10,100 positions - including 1,700 staffers in the US and 8,400 internationally - are to be classified as “Attrition w/o backfill”.
The relevant dictionary definition of attrition is "the process of reducing something’s strength or effectiveness through sustained attack or pressure". In the case of IBM, it will not replace staff as they leave or their contract position is stopped/ not renewed.
Presumably IBM is basing this figure on previous years' data - the relentless grind of repeated redundancy programmes across GTS has seen morale on the shop floor deteriorate. Perhaps this will contribute to the numbers of heads that simply decide they've had enough and walk on.
Some 9,300 of those GTS positions (b-f on the chart) are to be redeployed to RFS, new business, cloud migration, pyramid roles and shoring roles.