I think an actual JAO might still be good in twenty years (I'm aiming to try the last bottle of my first JAO batch at age ten and I'm sure I will post my review if I do get to it in 2016) as it's sweet enough that the sugar in the honey will act as a preservative, but this is considerably weaker than that, 1000g = 1 kg = 2.2 lb and 5 litres is more than a gallon.
I find 1 kg honey in about a gallon gives me a SG of around 1.080, and yours is more dilute than that, I suspect it will finish dry, and will not have a high enough alcohol content (yours will be under 10%) for long-term aging, even with the chemicals I'm not sure it'd be worth keeping that long.
If you want to make something that will last that long, you'll probably want to plan for it and take a look at what others have done, there are a few good posts about it around here if you can convince the forum search engine to hand them over .
And welcome to the forum!
"The main ingredient needed is 'time' followed closely by 'patience'." - The Bishop 2013
"Good grief! If someone wanted to murder you, all they would have to do is ship you a 55 gallon barrel of honey and watch you document working yourself to death!" - Vance G
"When you consider that laziness and procrastination are the fundamentals of great mead, it is a miracle that the mazer cup happens." Medsen Fey, 2014