What if the Bitcoin fees alone spike beyond 0.0002 BTC for quick transaction confirmations? Won't you be operating in losses?
IMO it's not that difficult to find the solution for things like that. Either change the fee or use 1 sats/vbyte for every tx. I don't think they promise instant confirmation, just the 1-3 target (which could take hours or days if the mempool is busy). Can't say the customers will be happy with that though. If anything, I'd be more concerned about the strength of the encryption.