No, sorry. You'll need to actually move the OBB reservation as it can't be adjusted to another reservation (that you put on hold this morning). Depending how long you wait to make that decision, the price could increase.
If you know you want to move the OBB (no intention of sailing the current date), the move the OBB and it will still hold for 3 days while you decide if you wish to finalize the deposit. I guess the downside is that if you decide NOT to take that new cruise, you would need to move the OBB back to something with a lower deposit closer to what's already been paid.
Enjoy your cruise!