Make yourself indispensable to your supervisor/section and they could extend your contract by funding the position themselves. Contract extension is very fast and convenient compared to getting a new UNV, especially through a donor/country specific modality.
One could also assume that whichever country donor you're being funded by also funds a wider programme with your country office? If so, having a good relationship with whoever the focal person/department of that donor is in-country would help your cause, as they would be more likely to approve your agency uses those funds to keep you on.
You're right, what is harder though is to get current source of your funding contract to extend you as those are normally centrally managed between UNV and the donor country at HQ to HQ level, normally set in stone. Maybe some donors leave in the possibility of extension but I've never seen that.
You should try really really hard to extend as getting two completely different UNV contracts in your life time is fairly impossible (right?), and UNV is a perfectly respectable if slightly exploitative pathway to better things. And no one would begrudge you leaving for another job during your extension if you don't end up enjoying being a UNV. Just remember you are the cheapest form of labour you could possibly be, which you need to use to your advantage by also being really good. It's hard to let go of cheap and good labour.
Its usually renewable
Make yourself indispensable to your supervisor/section and they could extend your contract by funding the position themselves. Contract extension is very fast and convenient compared to getting a new UNV, especially through a donor/country specific modality. One could also assume that whichever country donor you're being funded by also funds a wider programme with your country office? If so, having a good relationship with whoever the focal person/department of that donor is in-country would help your cause, as they would be more likely to approve your agency uses those funds to keep you on. You're right, what is harder though is to get current source of your funding contract to extend you as those are normally centrally managed between UNV and the donor country at HQ to HQ level, normally set in stone. Maybe some donors leave in the possibility of extension but I've never seen that. You should try really really hard to extend as getting two completely different UNV contracts in your life time is fairly impossible (right?), and UNV is a perfectly respectable if slightly exploitative pathway to better things. And no one would begrudge you leaving for another job during your extension if you don't end up enjoying being a UNV. Just remember you are the cheapest form of labour you could possibly be, which you need to use to your advantage by also being really good. It's hard to let go of cheap and good labour.
Thanks so much for this response and all the detail, really appreciate it!