I'm not sure I understand the whole question. I'm confused by the 1/2 part.
If the service member is on the obligation (note), it should go to 6% and watch out for any fees that may also be "interest" under SSCRA. You can't reduce a proportionate share.
As to defering the debt in its entirety, good question. If you defered the entire payment stream you'd protect your earnings estimates, but would have a nonperforming loan in the interim. What if the service member takes an extended tour. Are you prepared to have a nonperformer for 3, 6, maybe 10 years? The customer could decide they like the service and reenlist.
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