Actually the fix is in the beta release that just went out this morning: Hub Firmware 0.40.X Beta
It was a leak for TLS sockets in general. Though there’s still currently a bug that means the TLS sockets count double against the limit, but once close both of those are uncounted, but you’ll have an effective limit of 128 TLS sockets for the moment.
And thank you for the bug report with a minimal reproduction. Getting those is so immensely helpful.