Static condensation with multiple load cases

Hi

I want to apply the static condensation on a problem with multiple load cases. 

In manual, 'p2gsub' keyword exists but there is no detail explanation about that. 

Please, let me know the process of static condensation with multiple load cases. (the cases of same SPC and different SPC)

I hope there is a smart way rather than the separation of model same as the number of load cases.