403(b) Plan Post-Merger - to Terminate or not to Terminate??

Two non-profit entities are merging - Employer A (the surviving entity) has a 401(k) plan and  Employer B has a 403(b) plan. 

I'm curious what others thoughts are on whether they should terminate the 403(b) plan or adopt it and freeze it? I generally prefer the termination of a target's retirement plan prior to a merger/acquisition to reduce liability, administrative costs, etc. But do the complexities of terminating a 403(p) plan outweigh the potential benefits here? 

I believe assets are held in a group annuity contract, but there may be individual annuity contracts (I am checking).