Upgrading from premium to Ultimate

So yesterday I got a notification when I opened my Avast dashboard that I could upgrade to Ultimate at a discount (pretty significant I might add). Because I was busy, I didn’t immediately click on the offer. That notice is now gone. Now that I’m interested, I wonder if there is a way I can upgrade my premium to ultimate from my dashboard? and whether I can check if whatever discount I was offered still apply?
Thanks.

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