Ouch. I bet warring factions are over-joyed about this.

my faction is loving this atm, cuz we dnt intend on warring however we hav a fool profe plan when the 31 days r over!! basically we r gunna war wid 50 ded or broken/weak faction, thus nt letting hard ass factions war with us
its fool proof!!!
(untill capitan CHED starts deleting them lol)

Thats a good idea tcb rocks except for one flaw... whilst you can only war against 50 factions, it's been stated repeatedly that 50 factions can declare on you. You're not allowed to start 50 wars, but that doesn't mean 50 you'll be restricted to 50 wars per faction war base.

Also can we somehow fix the TCB Forums?

TCB: Forum links fixed. Thanks!

Do you know if this can be used repeatedly?
(So, is it possible to be peaceful forever?)

TCB: As far as we know, yes, as long as you meet the requirements.

I used this on my faction.
We still had 63 days of peace left.
we also has 154 Respect taken for the cost of the upgrade.
We had 307 Respect before the upgrade.

And we still have the option to do it again. So I am guessing, it is like buying items form the shops. So long as you have the respect, you can purchase 31 days.

You're actually mistaken about it not letting you use this feature if you have over 250 respect. It's actually thus:

"Subsequently, 50% of your respect will be lost to gain 31 days of peace.
You must have over 250 respect to initially increase your peaceful time."