I think the key question here is "How long will they last in refrigeration?" I have not found an answer to that specific question yet.
1- Plant them now. Amend the soil before planting, give them good care and plenty of water while they grow leaves, blom, and for a few weeks afterwards. Then they will want to dry and go dormant.
2- Keep them in the refrigerator until fall, and plant as you meant to.
"Paperwhites" are usually sold for forcing indoors in the winter. Papaerwhites, when put in a dish for forcing, will make roots, leaves and a bloom. I have not seen them sold refrigerated and do not think it is necessary. (Side note- Paperwhites I have forced, and then planted outside, have lived but failed to bloom for two years now.)