Finding price/availability for upgradeable fare classes?

Hi all - is there a link on the VS website to easily search for upgradeable fare classes? Or some other resource?

I used to have a working link, but it's broken now, and there surely must be some other way than calling and pestering the phone agents to look at a large range of dates/options?! I simply want to review the price of specific S class PE fares, over the coming months, that I can upgrade with miles to UC. It seems VS don't want you to be able to easily search for these!

ps: the regular link that allows you to choose a 'Flexible' class PE ticket is always pushing you to a W fare - the most expensive PE class, when S are often much cheaper.
A W if often just a few pounds shy of a (non flexible) UC seat - so really it's nuts to buy that, unless you absolutely *must* have total flexibility.

Ok, I just tried with ITA matrix and got it to work, including specifying the ticket class.
amazing! I'm no expert at this, but plan to waste a few hours playing with it now...

Glad you found a way to search using ITA matrix. To answer your query, VS IT appeared to remove that search functionality some time ago. At the time it was the cause of much debate as many of us had bookmarked the link. Likewise we can't search for M fares in economy anymore either.