Yes, this has been frustrating. I did seem to find a temporary solution based on another post someone else made on the forums, and so far my profile is still in the right order.
1. Place all items in the reorder function that you want to finally have it, but have 2 that are next to each that you are fine with swapping later (probably best to be one of the lower priority ones)
2. Save changes and refresh page, and the items should be reversed the wrong way, like usual.
3. Open the reorder option again, but just swap those two that were picked out.
4. Save changes and refresh page.
Hopefully now it should be in the right order and stay that way. It has worked for me since I did it. I hope it works out for anyone else that tries it.
Although few days ago, it was not in my desired order, but now it is same order on upwork as it was on oDesk. And thank you upwork for providing reordering option with portfolio.
Sorry, if someone not liking it or even if they are required to reorder their portfolio 'again'. (Reordering option is available for you, if you want to reorder.)