There isn’t anything in the news that would indicate a problem -...

There isn’t anything in the news that would indicate a problem - in fact the opposite, projects being won and employment positions vacant.

Volume has been large in the last week. I can only conclude that a large holder has realised that Brookfield are unlikely to mature these within the next decade and are clearing their books for new hybrids coming out.
Whoever is buying seems to be getting a good investment - a fairly safe 8.6% running yield plus another 1-2%pa cap gain if you’re willing to wait long enough.