I believe thats a standard message, we’ve never experienced such a prolonged outage before so that message makes sense because in the past Internet Archive has been offline for a few hours tops. Sometimes it can also appear if the Internert Archive is overloaded, so in theory you could be lucky during those scenarios and have something be succesfully uploaded!
A lot of people are upset that its offline, but it will be back eventually - just need to give it time; however there is another thread about working on a contingency plan in case this occurs again.