Oh yeah, that’s the new hexadecimal IPV8

I often assume this kind of thing is part of an effort to filter for idiots

If you know that's an invalid IP address, you're probably less likely to fall for the scam after the scammer has put the setup work in. So if they filter you out before a scammer has to spend any actual effort on you, that means more time they can spend scamming people who might be more likely to fall for it

That's why these things often have egregious spelling errors and other seemingly obvious red flags

It's not often you see IPv5

In addition to what others have already posted, I suspect that this might be an attempt to evade spam/phishing filters that are looking for an IP address with a specific regular expression. Having a fake IP address that doesn’t match the traditional ^((25\[0-5]|(2\[0-4]|1\d|\[1-9]|)\d)\\.?\b){4}$ format might let this message slip through.

This is just an IPv5, they're quite rare in the wild

Took me a second to figure out what was wrong with the email... I choked on a laugh when I saw the IP

What a bizarre, narrow window of knowledge that person must have

New address space unlocked

For the uninitiated, the joke is:

Jesus Christ, that’s Jason Bourne’s IP address!

That's called Web 3.0

Sorry, that's my IP. I was trying something

Please, do not share the button. It's gross.

no shit they don't recognize that IP :-D but hey, they also single handedly solved the IP4 address space crisis!

86.75.30.9

Ok I admit I didn't get it at first because I expected the joke to be that the IP is 127.0.0.1 and didn't look closer at the digits

I think I see why the login attempt was unsuccessful!

Spain has better food, better beaches, hotter women, better fiesta, better weather, better lifestyle, better IP's.

Deal with it.

They just wanted to make doubly sure that whoever they are phishing is an idiot before they proceed further.

I was surprised to find that this doesn’t work at all.

For instance, 300 is considered a valid IP by e.g. Firefox, typing 300/ into Firefox will navigate to http://0.0.1.44/. I was expecting this to be interpreted as just Σ 256ⁿ × dₙ mod 256⁴. But it isn’t, Firefox won’t accept this (it performs a web search instead). Neither will curl (which tries to look up a domain by this name).

Probably outer space