If I delete my Unroll.Me account, what will happen to all of my previously rolled up emails?

No worries — we don't store any of your emails on our servers.
Since we access them via IMAP, they're stored safely in your email client. 

All of your previously rollup emails will remain in your "Unroll.Me" folder in your email client — even if you delete your Unroll.Me account. 

Here is an image of the "Unroll.Me" folder in Gmail: