The 777s (including the LR) ain't going anywhere any time soon, especially the majority of them that are owned directly by AC but I won't be surprised if we see A350(neo?) orders at the end of this decade, maybe even some A320/A321NEO when they become widely available in the used market.
AC's fleet strategies have always been very flexible, they buy/lease planes when the price is right, the E190s, the used A330s and A320 are the prime examples.

We had been talking about the A330's retirement since the late 00's and early 2010s, the A319/320 since the MAX.
Who would have thought we have more than doubled the amount of A330 flying today, "new" A320/321 continue joining the fleet, and the supposedly retired A319s are still flying around everyday.