I don't think we're going to see any push from BM to support SD 4:3 lenses on their 4K cameras.
That said many old lenses are capable of analog and serial/digital operation. The default shipping configuration is typically analog and there's a magic sequence to reboot the lens into serial mode. For example this (see attached) is the sequence for booting an ancient (~20 years) standard def Fujinon A22X7.8 lens into serial mode.
Whether or not the J55 Canon supports serial (maybe that's what makes the Digi-Super Digi?) or what the process is I can't say. Anytime I've called Canon they've been helpful and forthcoming with information so it may be worth a shot.
As an alternative, Kim Janson has developed an interface to overcome this limitation.
viewtopic.php?f=4&t=165607&p=894439&hilit=analogue#p894439Good Luck
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