Quote from Yogurticecream;231086:
There's a release bag option.
I read from somewhere (I think it's mabinogiworld wiki) that you can still use the crystals in the bag after it expires though, just that you can only access those crystals by using the skill...
The same applies for Phoenix Feathers, enchanting options, and ego feeding options when a normal bag expires.
The only problem is not knowing what's left in the bag, although that shouldn't be much trouble now that we have ammo counters.