I'm anxious to delete and restore using my seed phrase just yet.
You don't need to.
Updating the application does not erase the user data.
I've been reading reviews of the app in the app store and quite a bit of them are indidivuals complaining that they restored their MyCelium wallet using their pass phrase and their bitcoin balance inside the restored app was now zero.
Those reviews are most likely from people who failed at backing up their mnemonic code properly.
I have quite a bit of BTC in this wallet and don't necessarily want to do anything too quickly (although I know that restoring from the pass-phrase is objectively the correct thing to do in this case).
In this case, you might want to make a backup of your current wallet.
I guess you are aware of the risks storing crypto on a mobile wallet as opposed to a desktop- or hardware wallet?
I've had errors with MyCelium in the past and they have usually self-corrected, and have been able to find a few individuals today who had a smiliar problem. Still troubleshooting with them.
This might also be the case now.
If you aren't in a hurry, just wait a day or two. If you are in a hurry, use your mnemonic code to restore your wallet on your desktop system (e.g. via electrum).