As to OP, I will assume you are upgrading your pack, and therefore have your older pack to use. So if your new gear comes before your next trip then great! But if your pack is delayed, hey you’re still out hiking, and you will appreciate your new gear even more when it does come. You have an enviable problem!
that said, hope your new gear comes in tomorrow. Where are you hiking? If you are starting a thru hike, perhaps you can get the pack shipped in to one of the hostels, hold for thruhiker.
and, a good reminder to us all to build in adequate lead time.
Enjoy your journey :*)