PM8 "shares", on the ASX, aren't actually shares. They're Chess Depositary Interests (CDIs), at a 1:1 ratio. This means that legally, the shares are owned by the ASX CDN (CHESS Depositary Nominees Pty Ltd), but all beneficiary interests are passed through to the holders of the CDIs.
So, assuming that Pensana de-lists from the ASX, all the CDIs will be converted, 1:1, to PRE shares on the London Stock Exchange. There'll be options for holders to cash out rather than take the conversion. It's possible to do the conversion right now (in either direction - meaning you can convert a PRE holding to a PM8 holding, and vice versa), but there's no benefit in converting a PRE holding to PM8, given that (a) they're trading over there at a higher price, and (b) it looks very likely that PM8 CDIs won't be around much longer.
